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3+ nonpolar covalent bond examples: Detailed Insights And Facts

January 20, 2024December 30, 2021 by Sania Jakati

In this article, we shall see 4 nonpolar covalent bond examples.

Nitrogen (N₂)

As we know Nitrogen is discovered by the renowned scientist Daniel Rutherford ( year 1772) . He obtained it by removing carbon dioxide from the products of breathing animals in closed space.

Occurrence

Elementary nitrogen constitutes three-fourths of air by mass or four-fifths by volume. Also found in KNO3 form ( quite abundant) , NaNO3various salts of ammonia. As we know Nitrogen is a very crucial element for us either we take it directly or indirectly. By plants or animals as source .

nonpolar covalent bond examples — **nonpolar covalent** **bond examples**
**Image Credit : Chemspider**

Preparation of Nitrogen

Nitrogen is conveniently prepared in the laboratory by the following methods :

(a) By heating a Solution containing Ammonium and Nitrite Ions

A solution containing equivalent amounts of ammonium chloride and sodium nitrite is warmed in a round bottom flask fitted with a thistle funnel and delivery tube. Nitrogen gas is evolved and is collected over water.

(b) By Oxidation of Ammonia.

Nitrogen is also obtained by oxidation of ammonia with red hot copper oxide or chlorine. In each case hydrogen is removed and nitrogen set free.

Nitrogen is also formed in a number of other reactions, the more important of which are given below :

(i)Ammonium dichromate ( usually red color crystals ) when are heated give out light ( flashes) and thus required substance is formed ( Nitrogen is left behind.

The reaction is employed for the demonstration of the eruption of volcano. For this purpose, a heap of ammonium dichromate is ignited by touching the top with a hot wire (volcano experiment).

(ii) Nitrogen is also evolved when urea is heated with an acidified solution of a nitrite.

(iii) In the presence of an alkali, sodium hypobromite, NaOBr, liberates nitrogen from ammonium salts or urea.

(iv) Very pure nitrogen is obtained by heating sodium azide, NaN₃, when it decomposes into its elements.

Process.

Carbon dioxide is compressed ( at 200 atm pressure) after that it is cooled by the process of passing it through a pipe which is surrounded by water ( cold ) . This air(which is cold as well as compressed) is made to pass through spiral followed by Joule- Thomsan effect.

This cool air passes up surroundings the spiral pipe and cooling down the coming air there in. This cooled air passes up surrounding the spiral pipe the coming air therein. Furtehr cooling takes place by expansion. The upgoing air is compressed once again and recirculated.

Nitrogen and oxygen are manufactured by the fractional evaporation of this liquid air by Claude’s process given below :

Claude’s Process, Principle

When a cold compressed gas is allowed to do some external work, e.g., pushing the piston of a gas engine (adiabatic expansion), it falls in temperature (cf. Joule-Thomson effect where in work is done against intermolecular forces).

Process.

Air is filtered to remove dust particles and compressed to about 60 atmospheres all above. It is cooled to remove the heat generated on compression. The compressed air is freed from carbon dioxide by passing through a tower packed with soda-lime and then dried by passing through alumina driers. It is next passed through pipes surrounded by cold nitrogen or cold oxygen in heat exchanger.

The cold compressed air is allowed to do work in Claude’s expansion engine when it is partially liquified. High operating pressure of the order of 140-150 is used, and air at 150 atmospheres and 248 K is expanded in this way to 6 atmospheres and 103 K when it is partially liquified.

The partially liquified air is passed through a double rectification column. In the lower column, the fraction of air not previously liquified and from the liquid air at the base rise up. These gases are richer in nitrogen, i.e., the more volatile constituent.

As the upgoing gases pass into the closed space and are forced to move down through the outer pipes surrounded by liquid oxygen, nitrogen being at 6 atmospheres condenses. Some of this liquid nitrogen is removed from here and used.

The rest passes through an expansion valve and expands to 1-atmosphere pressure. Liquid nitrogen is poured at the top of the upper column. Liquid air at the base containing about 40% oxygen is also expanded to 1 atmosphere and poured near the middle of the upper column.

As the liquid falls down the fractionating column, it meets an upward stream of gases. The liquid is warmed a little as it is coming down and loses more and more of volatile constituent, nitrogen, by evaporation and gets richer and richer in oxygen. After this process the required quality (purity) Nitrogen can be obtained.

Read more about : Alkyl Halide Examples: Detailed Insights And Facts

Nitrogen Tetroxide

It is very crucial ( substance) for preparing many other compounds .

Preparation:

It can be prepared by the oxidation process (catalytic) of the compound ammonia. In the step one of preparation, oxidation of ammonia nitric (oxide) takes place.

The water in it (almost all of it) is condensed, the gases present are cooled. The obtained nitric (oxide) is now oxidized, giving out nitrogen dioxide; after this dimerization process of this obtained nitrogen dioxide takes place, giving us the desired compound nitrogen tetroxide.

Another way for preparation is by using arsenious acid (which is in the hydrated form is used) kept in tabulated (which is in the bent neck form), and nitric (acid) is added to it. This particular mixture is warmed (slightly).

The gas that is evolved is made to pass in a bottle (wash bottle) which is later dried by using calcium nitrate (which is in the anhydrous form). The entire mixture is cooled, giving us a green (dark shade) liquid, to which dry oxygen gas is pumped (in an appropriately sealed tube)—finally giving out the required product.

Properties

Its appearance is a red-brown color (usually liquid) with not so good smell.
It has quite a low boiling point (recorded at about 21.15 degrees Celsius), sharp melting point (recorded at about 11.8 degrees F)
The nitrogen tetroxide molecule is planar in nature (the N-N bond length recorded to be 1.78 Å, and the N-O bond length recorded at about 1.19A degrees)
It is diamagnetic in nature (with no unpaired electrons).

Uses.

Nitrogen tetroxide has the ability to undergo autoionization (molecular). Many anhydrous metal (that of transition) complexes (having nitrate) are prepared:

The preparation of metal (nitrates) using N2O4 is carried out in anhydrous (condition).

Being an oxidizing agent, N2O4 is very crucial and is used in rocket propellants as it can be kept at room temperature without any hustle.

Read More about : SN1 Examples: Detailed Insights And Facts

Dinitrogen Difluoride

It was discovered in the year 1952.
It has the ability to exist in the cis and trans form.

Preparation:

The reaction of N, N – disfluorourea, and potassium hydroxide (concentrated solution) gives Dinitrogen Difluoride (reaction is carried out in aqueous)

One more method is the reaction of difluoramine and potassium fluoride (note that difluoramine is said to give a solid compound which is unstable in nature) upon the process of decomposition gives the required product, i.e., dinitrogen difluoride. (In place of potassium fluoride, we can also use rubidium or cesium fluoride as a substitute.

One more method by the process of photolysis (using tetrafluorohydrogen with bromine).

It can be prepared by reacting N2O4 with a mixture (metal carbonyls and carbon monoxide) at a temperature of 175 degrees Celsius.

Properties

It is a colorless gas at a recorded molar mass of 66.01 g/mol and has a density of 2.698g/L.

Its observed melting point is -319.0 degrees F and -172 degrees Celsius for cis and Trans types of structure, respectively.

Its observed boiling point is -158.35 degrees F and -111.45 degrees Celsius for cis and Trans type structure, respectively.

Isomerism:

The symmetry of the cis form is C2V, and that of the trans form is said to be C2h. The isomers are observed to be interconvertible (by the thermal process).

The cis and trans form are separable by fractionation (carried out at quite a low temperature).

The Trans form of nitrogen difluoride is recorded to be less stable (in terms of thermodynamics), and it is possible to store it in a glass vessel.

About the reactivity of cis form of nitrogen, difluoride is it has the potential to attack glass in time (of two weeks) and (gives silicon tetrafluoride + nitrous oxide)

Nitrate: (NO3- )

It is considered a polyatomic ion, and the salts comprising this particular ion are referred to as nitrates.

opo nitr — **Image Credit : Fisher Scientific**

Preparation:

-Nitric acid is a vital component in the preparation of nitrate.

-Also naturally occurring as nitratine in the earth (deposits).

-Are prepared by considering sources of nitrogen (ammonia or urea) by bacteria (nitrifying) available in nature.

-By the process of fermentation (of urine and dung)

-When lightning strikes the earth’s surface (in nitrogen-oxygen) rich atmosphere, a whole lot of oxides is produced later washed by rain from the atmosphere.

Detection

It can be detected by the method of colorimetry. Usually, estimation/detection is based on the diazotization process involving naphtylamine. Nitrates under acidic conditions diazotize sulphanilamide to occur and product coupled with N-1-naphthyl etheylinediamine dihydrochloride. (Note the first nitrate is converted into nitrate form).

Uses:

Used in many fertilizers (in the agro-industry).
Being great oxidization agents used in explosives
What effects can nitrates have on our bodies?

As we know, nitrates are an essential part of our diet, but everything has to be within limits. If it is too much, or too less, both ways, it can harm us.

If we consider drinking water, the standard amount of nitrate tolerable in water is 10mg/l. Above this can pose to be dangerous.

Problems:

Which of the above substance occurs in isomer form ?

Ans Dinitrogen Difluoride

Which compound can be prepared by following Claude’s process? and Which of the above mentioned compound has the ability to undergo autoionization ?

Ans Nitrogen and Nitrogen Tetroxide

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Are Protists Eukaryotic: Why, How And Detailed Insights And Facts

January 23, 2024December 29, 2021 by Sugaprabha Prasath

Protists are mostly single-celled or unicellular organisms mostly live in aquatic ambience.

Protists are eukaryotic mostly single-celled or unicellular organisms. Though they are relatable to other organisms they aren’t considered as true animals, plants or fungi this is why they fall into a different category.

Why are protists eukaryotic?

Now we know that protists are mostly single-celled organisms but still what makes them fall under the category of eukaryotes.

Protists have a nucleus and other complex organelles in them which makes it fall under eukaryotes.

Why are protists eukaryotes and not prokaryotes?

Protists are mostly single-celled organisms and still, they come under eukaryotes. We know that prokaryotes are simple and eukaryotes have complex structures. But protists are eukaryotes, how?

The presence of a nucleus inside them and other complex membrane-bound organelles make protists fall under eukaryotes.

Are Protists Eukaryotic
Image credits: Wikimedia

Are protists simple or complex organisms?

Protists, though they are mostly unicellular organisms, they are not simple organisms.

Yes, protists are complex organisms. They have complex organelles in them which are similar to plants, animals, fungi and other bigger organisms.

Are protists haploid or diploid?

Protists can be haploid or diploid.

Protists transform themselves from being haploid to diploid.

Most of the protists are unicellular which are haploid. Multicellular protists are diploid. This may change from one species of protists to another depending on their morphology and other components.

Are protists motile or nonmotile?

Motility or movement of small organisms is based on the presence of flagella, cilia, pseudopodia (False feet) in the protists.

Most of the protists have flagella and have the capability to move.

Eg: Flagellum- Euglena, Pseudopodia- Amoeba, Cilia- Paramecium.

Euglena diagram — Euglena
Image credits: Wikimedia

How do protists obtain energy?

Based on their nutrition uptake, protists are classified into 3 types

Ingestion protists
Absorption protists
Photosynthetic protists

Ingestion protists:

This group of protists engulf the minute food particles and ingest them. The food particle is then digested in the organelle called vacuoles.

Eg: Amoeba

Figure B23 02 01 — Ingestion protists
Image credits: Wikimedia

Absorption protists:

This group of protists are called decomposers. The food particle is absorbed into the organism by the process of diffusion.

Eg: spirogyra

Photosynthetic protists:

Photosynthetic protists are the group of protists that are able to prepare their own food by the process of photosynthesis in which light is used as a primary source. They are the producers and are majorly present in the aquatic system.

Eg: Algae, diatoms, dinoflagellates etc.

What protists are decomposers?

Protists are producers majorly. Few protists are decomposers too.

Slime moulds are decomposers. Other than slime moulds, chytrids, Oomycetes, labyrinthulomycetes are other examples of protists being decomposers.

Are protists aerobic or anaerobic?

Protists can be aerobic or anaerobic. Few protists are obligate aerobes. Few are anaerobic organisms

Characteristics of protists:

Protists are mostly single-celled organisms or commonly known as Unicellular organisms.
There are few multicellular protists too.
Protists are complex organisms as they have nuclei inside them.
Protists have other membrane-bound organelles like endoplasmic reticulum, mitochondria, vacuole etc
Protists are mostly motile. They have flagellum, cilia or pseudopodia which is commonly called “False feet”.
Protists require a moist environment to survive. So they are aquatic organisms.
Few protists have symbiotic relationships. They live like a parasite inside other organisms like plants, humans etc.
Based on their nutrition uptake, protists are classified into 3 types: Ingestion protists, Absorption protists, Photosynthetic protists.

Importance of protists in Ecology:

They involve themselves as a major part in food chain
Protists have the capability to consume/ ingest bacteria and other microbes. This way the microbe population will be under control.
The photosynthetic protists play a vital role in ecology as they aid in reducing atmospheric carbon dioxide.
The major protists, Phytoplankton is the basic component of marine food chain.
Protists aid in building coral reefs.
Protists aid in recycling nutrients in the ecosystem.

Importance of protists in the Economy:

By the process of photosynthesis, Protists release oxygen. This can be used for biofuel preparation.
Few protists like Red algae etc. have medicinal value.
Protists like seaweeds are consumed in many countries like Japan etc. They can also be used as a fertilizer as they are rich in potassium, nitrogen etc.
Diatoms are used in making paper, cement, dental impressions etc.
Agar agar is a red algae used in growth media in microbiology and as a thickening agent in food industries (Jams, jellies etc.)

Read more on Eukaryotic examples

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Do Bacteria Have DNA :Why,How And Detailed Insights

January 23, 2024December 13, 2021 by Piyali Das

Bacteria are one of the large groups of free living prokaryotic microorganisms. They possess a prokaryotic kind of cellular structure. Here we will try to find the answer of do bacteria have DNA and do bacteria have ribosomes.

All bacterial cells have DNA or deoxyribonucleic acid in their cytoplasm as their genetic material.

The bacterial DNA structure is slightly different from eukaryotic DNA molecular structure.The bacteria also have ribosomes in their cytoplasm as the protein factory of their cell.

Do bacteria have DNA?

DNA is the main genetic meterial in all living beings. It pases genetic information from generations to generation.

Bacteria have DNA. Bacterial cells have a naked circular single DNA chromosome in its cytoplasm. This is the genetic material of that organism.

In addition to this bacterial cells also have an extrachromosomal DNA, called plasmid DNA in their cytoplasm. This Extrachromosomal DNA provides some genetic advantages to that organism.

Bacterial DNA from pixabay

What is DNA?

The word DNA stands for deoxyribonucleic acid. It is composed of polynucleotide chains.

DNA carry genetic information in an organism. It consists of a deoxyribose sugar molecule, nitrogen containing nucleobases and a phosphate group.

All organisms such as archaea or bacteria have circular single chromosomal DNA in their cytoplasm.

What are the components of DNA?

The two polynucleotide chains coil to form the DNA double helix. The polynucleotide chains are antiparallel and made up of monomeric nucleotides.

Deoxyribonucleic acid or DNA made up of a deoxyribose sugar molecule, nitrogen containing nucleobases and a phosphate group.

The nucleotides have one of the four major nucleobases that are purines such as adenine (A) and guanine (G), pyrimidin such as thymine (T) and cytosine (C). The nucleotides are binds with each other by phospho-diester linkage bonds between a sugar of one nucleotide and phosphate of another. The nitrogenous bases (Adenine with thymine and guanine with cytocine) of two polynucleotide chains bound together with hydrogen bonds. According to basepairing rules one purine and one pyriimydin joins with hydrogen bonds. Adenine pairs with thymine with hydrogenous double bond and guanine pairs with cytocine with hydrogenous triple bonds. The two polynucleotide strands carries same genetic informations.

What is genomic DNA in bacteria?

The genomic DNA or chromosomal DNA of bacteria is the main genetic material of that organism. It carries almost all the genetic instructions in it.

The genomic DNA or chromosomal DNA is a naked ( not bound with any kind of proteins) circular double stranded DNA. It is continuous, which means it has no free ends (telomere).

It doesn’t have any histon protein. The genomic DNA is larger in size than the plasmid DNA. It’s size varies from about 130 kbp to over 14 Mbp. It encodes all the genetic instructions related to growth, development and reproduction. It can be transferred through the cell division process.

What is plasmid DNA in bacteria?

Distinct from chromosomal DNA bacterial cells have another kind of extrachromosomal DNA that is plasmid DNA in their cytoplasm.

This special kind of DNA material provides that organism some special genetic advantages like antibiotic resistance.The plasmid DNA is smaller than the chromosomal DNA in size from 1 to over 200 kbp. The number of plasmid DNA in a single cell varies from 1 to 1000.

It carries some additional genes which encodes genetic information that is genetically beneficial to those organisms and helps in their survival (antibiotic resistance). Plasmid DNA has its own origin of replication, which means It can replicate independently. It is transferred only by the horizontal gene transfer.

Do all bacteria have DNA?

Yes, all bacteria have DNA as their genetic material.

They have different forms like chromosomal DNA, mitochondrial DNA, plasmid DNA, etc.

Why do bacteria need DNA?

All living organisms including bacteria all need DNA in their cells. As a genetic material the significance of DNA or deoxyribonucleic acid in an organism is immense.

DNA or deoxyribonucleic acid is the carrier of all the genes in a cell. That means it carries all the genetic instructions in it.

The genetic codes in DNA responsible for making every required protein molecule in cells.

Through the replication process the DNA makes identical copies of itself and transfers. It carries all the genetic instructions from generation to generation.

DNA acts as a template for the RNA synthesis process.

The DNA is responsible for every biological activity within the cell ( directly or indirectly).

DNA is also responsible for cell aging or cell death.

To know more about Bacterial DNA Replication check out this article Bacterial DNA Replication Steps.

DNA replication from pixabay

How much DNA does bacteria have?

As we already discussed, all bacteria have DNA. The amount of DNA varies from species to species.

For example, the amount of chromosomal DNA in Mycoplasma genitalium ranges about 580,000 base pairs.

In Escherichia coli the amount is about 4,700,000 base pairs and in case of Myxococcus xanthus it ranges about 9,450,000 base pairs.

What is DNA polymerase?

DNA polymerase is a class of enzymes necessary for replication of DNA.

DNA polymerase catalyzes the chemical reaction of the replication process. During cell division it reads the template DNA strand, creates identical copies of it by adding nucleotides and completes the replication process with the help of other groups of enzymes. It also performs some DNA repair mechanisms.

How many DNA polymerases do bacteria have?

DNA polymerase I

DNA polymerase II

DNA polymerase lll

Bacterial cells have three DNA polymerase enzymes which are extremely important in DNA replication and DNA repair processes.

DNA polymerase I : In 1956 DNA pol l was first discovered by Arthur Kornberg. It is one of the main enzymes for the bacterial replication process. It is encoded by the gene called polA. It also supports DNA repair mechanisms. It makes short DNA stretches, replacing that with RNA primers during excision repair mechanism. It also helps to join okazaki fragments in the lagging strand. The DNA pol l can add about 15 to 20 nucleotides per second.
DNA polymerase II : In 1970 Thomas Kornberg isolated a DNA polymerase enzyme belonging to the B family of DNA polymerase, called DNA pol ll. It is encoded by the gene called polB. It has both endonuclease and exonuclease capabilities. It can synthesize DNA from both the directions. It also performs primase activities. The DNA pol ii is very important for DNA proofreading mechanisms.
DNA polymerase lll : In 1970 DNA pol iii was discovered by Thomas Kornberg and Malcolm Gefter. It is the primary holoenzyme complex for the bacterial DNA replication process. It plays a major role in synthesis of daughter DNA strands. It can add about per second. It has endonuclease and exonuclease capabilities. It can also possess a proofreading mechanism. It has the highest polymerization rate that means it can add about approximately 1000 nucleotides per second.

How many genes does a bacteria have?

The number of genes in a bacterial cell varies in different species.

According to a study, parasitic bacteria may have 500–1200 genes, free-living bacteria have 1500–7500 genes, and archaea have 1500–2700 genes in their genome.

In Escherichia.coli bacteria 4288 annotated protein coding genes, seven rRNA operons, 86 tRNA genes can be found.

Do bacteria have ribosomes?

Yes, bacteria cells have ribosomes in their cytoplasm. The bacterial cell is composed of 70S ribosomes which have the smaller subunit 30S and larger subunit 50S.

The bacterial ribosomes are about 200 nm in diameter. It is a nucleoprotein present in cytoplasm which helps in protein synthesis.

What are ribosomes?

In 1950 the famous Romanion-Americn cell biologist Gourge Emil Palade first discovered ribosomes.

Ribosomes are protein molecules present in cytoplasm. It mainly helps in mRNA translation and protein synthesis process. As it plays a major role in translation ,the ribosomes and its associated molecules are known as translation apparatus.

Ribosomes are composed of two different molecules, that is ribosomal RNA (rRNA) and protein molecules. Ribosomes have two different subunits. In the case of eukaryotic cells, the 80S ribosome has the small subunit 40S and the large subunit 60S. In the case of a prokaryotic cell the ribosome is 70S ribosome, which comprises 30S and 50S subunits. Where the S stands for a unit of density that is the Svedberg unit.

Where are the ribosomes found?

The ribosomes are found in two different forms, it can be free or it can be attached with an endoplasmic reticulum.

In case of prokaryotic organisms the ribosomes are present only in free form within the cytoplasm.

In case of eukaryotic cells the ribosomes are found in both forms. It can be present in cytoplasm as a free molecule and also present with the endoplasmic reticulum.

What are the functions of ribosomes?

Translation: The ribosome plays the main role in the translation process. The ribosomes decode the message from the m-RNA and by adding proper amino acids with the help of t-RNA synthesizes a protein molecule required to the cell.

Cotranslational folding: Ribosomes play a major role in cotranslational modifications of protein molecules. It has protein folding activities in it.

Addition of translation independent protein molecules.

As a whole we can say that bacterial cells possess DNA as their genetic material and ribosomes as protein synthesizers of their cell. Here we briefly describe all possible aspects of it. We try to give a clear idea about do bacteria have DNA? describe the features and functions of it. We also discuss about bacterial ribosomes, their features and some important functions. Hope this article will be helpful to you.

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What Can Exert A force: Exhaustive Insights and Facts

January 21, 2024December 7, 2021 by SAKSHI KM

Can an inanimate object exert a force In this article, we will discuss What Can Exert A force.

Force is a push or pull induced by the interaction between two objects. So, it is true to say that force can be exerted by the interaction of two objects. Once the interaction ends, objects do not experience the force anymore. Interaction is the fundamental way for forces to arise.

But the question arises that What Can Exert A force or of what kind of interaction should take place between two objects to exert force or Can an inanimate object exert a force . Do it necessary to establish a contact between two objects to exert force or force can be exerted by any kind of interaction.

To understand it in a better way, all interactions between objects are divided into two broad categories:

Contact force

When two interacting entities are considered to be bodily engaging with each other, contact forces occur.

“Frictional forces, tensional forces, normal forces, air resistance forces, and applied forces are all examples of contact forces”.

Can an inanimate object exert force: What Can Exert A force — Image credit:
What can exert a force

The force produced from the action at a distance (non-contact force)

This type of force is experienced when two objects are not bodily engaged with each other but can still impose a push or pull regardless of their bodily separation.

Gravitational force is example of force produced due to action at a distance. Sun and other planets have a very large distance between them but still, there is a force exerted by the sun and planets on each other. This force between the sun and other planets is also an example of force-producing from the action at a distance.

When we walk and our feet leave the earth’s surface and are no more in touch with the earth, even then there remains a gravitational force between our feet and the Earth.

Electric forces also act at some distance. After having short distance separation, protons inside the nucleus and electrons outside the nucleus feel a force of attraction with each other.

On the other hand, Magnetic forces are action-at-a-distance forces. Two magnets, for example, can exert a magnetic force on each other despite being distanced by only a few centimeters.

Do all objects exert force ?

What Can Exert A force?

All objects exert force on each other while they are bodily engaged but even if two objects are not in physical touch, they exert a gravitational force of attraction on each other.

True, however, humans aren’t aware of such forces since nobody on Earth has an enormously high mass. As a result, the force of gravity among the two items is so small that they are undetectable. Since the attractive force of gravity between two bodies in a place is relatively low due to their modest masses, they do not push or pull towards one other.

The force of gravity is used by objects with mass to exert forces on one other.

“Magnitude of this force is directly proportional to the product of masses of two interacting objects and inversely proportional to the square of the distance between them.”

Newton’s law of Gravitation: $F_{g}= -\\frac{GmM}{r^{2}}$

For all masses at the Earth’s surface, the parameters G, M, and r are the same. These components are added together to get the constant g, which we refer to as the acceleration due to gravity.

$g= \\frac{GM}{r^{2}}=\\frac{6.67\\times 10^{-11}Nm^{2}/kg^{2}\\times 5.98\\times 10^{24}kg}{(6.37\\times 10^{6}m)^{2}}=9.8 m/s^{2}$

The force of gravity imposed by the Earth on a body of mass m has a value of mg and is aimed downwards at the Earth’s surface.

Can an inanimate object exert a force ?

Yes, even inanimate objects can exert force. When you stand on a trampoline, for example, the trampoline deforms under your weight, exerting an upwards pressure on you to keep you from falling through.

Because the interactions between atoms and molecules are similar to those between the spring and stretchable fabric that make up a trampoline, when a pencil is placed on a desk, both the pencil and the desk are somewhat distorted. Although the distortion is too slight to see, the forces that cause it to keep the pen from going through the desk.

Does a physical object have to exert force ?

As we discussed before that the force is a push or pull and occurs due to interactions of two bodies.

Equal and opposing action-reaction force pairings are always present. For example; Nature has a wide range of action-reaction force pairings. Consider a fish’s ability to move across the water. The fins of a fish are used to push water backward. On the other hand, a push on the water will simply serve to speed it.

Because reciprocal contacts produce forces, the water sh\uld likewise be forcing the fish ahead, propelling it through the water. The pressure felt by water is same as the pressure felt by fish in magnitude but the direction of the pressure felt on water is backwards while direction of pressure felt by fish is forward. There is an equivalent (in size) and opposing (in direction) response force for every action. Fish can swim because of action-reaction force pairings.

According to newton’s third law, “For every action, there is an equal and opposite reaction.” Or Force occurs in pairs and they act on different bodies.

This law means that for every interaction, two main forces are operating on the two engaging bodies in each interaction.

“The forces acting on the first object are equivalent to the forces acting on the second object. The force on the first object is directed in the opposite direction as the force on the second object.”

Can a particle exert force on itself ?

In classical physics, particles do not apply forces to themselves since the classical models that were efficient at forecasting the state of systems did not need them to do so.

In classical mechanics, one might now establish a rationale. According to Newton’s laws, every action has an equal and opposite response. If I exert 100N of force on my table, it responds by exerting 100N of force in the other direction.

Consider this: a particle that exerts a force on itself is then pushed back in the opposite direction by itself with an equal force. It’s as though you’re squeezing your hands together tightly. You exert a great deal of power, yet your hands don’t move since you’re simply pushing against yourself. You push back every time someone pushes you.

In quantum mechanics, things are starting to get more fascinating. Avoiding digging into the finer details, quantum physics reveals that particles do interact with one another. And they have to interact with their interactions, and so forth. So, if we get down to the most basic levels, we can witness significant particle self-interactions. This self- interaction of particle is not observed in classical mechanics.

Can a block exert a force on itself ?

A body cannot accelerate itself by exerting a force on itself. If it could, things would’ve been able to speed without having contact with their surroundings. Pulling on your bootstraps will not help you get up.

The conservation of momentum is similar to the statement that the resultant force in a closed system is zero, and the law of conservation of momentum may be inferred from the uniformity of space. A mathematician named Emmy Noether confirmed this fact a long time ago.

Newton’s Second Law states, “the time rate of change of the momentum of a body is equal in both magnitude and direction to the force imposed on it.”

So by this law, a body cannot exert a net force on itself. If you exert a force F on your body with your hands, your body will exert an equal and opposite force F on your hands, resulting to the net zero force on your body.

Why do particles exert force

Because of the close proximity of particles, particles exert a powerful force force.

The particles are held very held together and they interact with each other. Their connection resulted in an attractive force between them. The intermolecular force of attraction attracts particles. This force is very powerful.

Why do charges exert forces on each other

As we study electrodynamics, charged particles interact with each other.

Charged particles have an intrinsic fundamental property that like charges repel each other and unlike charges attract each other, a force called electrostatic force is brought among charges due to this intrinsic property of charges.

This force is quite similar to the Gravitational force of attraction but the basic difference between the two is coulombs force can be repulsive as well as attractive while the gravitational force is only an attractive force.

“This force is directly proportional to the product of the mass of charges and inversely proportional to the square of the distance between those two charges”.

The electric field might also explain this. The features of the space enclosing a charged body vary, allowing it to function as an interaction channel among two charged bodies applying force on one another.

How does air inside a container exert pressure

Because of high kinetic energy and negligible force of attraction or weak intermolecular forces, gas particles can move in every direction at very high speed.

Due to the strong random mobility of the particles, they collide with one another and with the container’s walls. The pressure on the container walls is caused by the interactions of the air molecules with the container walls.

Why can’t a body exert a net force on itself

Because of newton’s second law of motion

If you exert a force F on your body with your hands, your body will exert an equal and opposite force F on your hands. As a result, there is no net force operating on your body.

So by this law, a body cannot exert a net force on itself.

Frequently asked questions| FAQs

Q. How do you find the force an object exerts?

One can calculate the force exerted on an object using newton’s second law of motion

Newtons are used to measure force, kilograms are used to measure mass, and meters per second squared are used to measure acceleration.

“The force applied by a body is proportional to its mass times its acceleration”: F = m a. You must use SI units to use this formula

Q. What are some examples of force pairs?

Cars can travel along a highway surface thanks to action-reaction force couples.

As a car moves on the road, the wheel holds the road and exerts a force backward on-road, and the road exerts a force on wheal in forwarding direction. This is a classic example of action-reaction force.

“For every action, there is an equal and opposite reaction.”

Q. What force the object will apply in reaction of the force applied by you on object?

Will be equal and opposite

All forces acting on two objects are of equal magnitude and opposing direction. Only one of the two bodies determines the amount and direction of the forces in particular cases. If you apply a force on an inanimate item, you will also define the force that the object imposes on you – a force that is equal to and opposite to yours.

Q. How many types of fundamental force are there?

Fundamental forces are divided into four categories. Four basic forces determine how things or particles engage and how some particles decline: gravitational, electromagnetic, strong, and weak.

Also Read:

Is Magnetic Field And Magnetic Force Same: Different Aspects And Facts

January 20, 2024November 28, 2021 by SAKSHI KM

Magnetic field and magnetic force go hand in hand. In this article, we will discuss the fascinating relationship between these two.

A magnetic field is an actual entity that fills up the space around a current-carrying conductor or moving charge, or magnet. In addition to this the force acted by a magnetic field upon a moving charged particle is magnetic force.

How magnetic field is connected to magnetic force

To understand it more precisely, if we place a static charge in a magnetic field, the charge experiences no force, so to define a magnetic field, we take a charge q which is moving with velocity v in such a field

$Fig. 1(a)$

Is magnetic field and magnetic force same

If F_m is the force exerted by the field on the moving charge, then it has been experimentally found that;

F_m ∝ v
F_m ∝ q
F_m ∝ v sinθ

If F_m is the force exerted by the field on the moving charge, then it has been experimentally found that;

Combining the above three points, we obtain

F_m= Bqv sinθ …………(1)

Here B is the proportional constant, and it gives the magnitude of the magnetic field. It is also known as magnetic flux density or magnetic field induction, or simply magnetic field. It is a pseudo-vector, and we denote it by B.

When a magnetic field is exactly equal to magnetic force

If we consider q=1, v=1 and θ = 90⁰

From equation (1), F_m= B

So here, we can say that the magnetic field at a point is thus equal to the magnetic force acting on a unit charge when it is moving with unit velocity in a direction perpendicular to the magnetic field.

In vector notation, F_m= q(B x v)

Obviously, F_m known as magnetic Lorentz force, is perpendicular to the plane containing v and B.

In case,

In that case,F_m= qvB

As, F_m= qvB

B= F_m/qv

If F_m = 1N, q=1C and v = 1m/s

Then, 1T= N/C(m/s)

1T= N/Ampere

The SI unit of B is called tesla(T)

So, the magnetic field at a point is thus said to be one tesla if a charge of 1 coulomb when moving perpendicular to the direction of the magnetic field with a velocity of 1 meter/second, experiences a force of 1 newton.

Direction of magnetic field and magnetic force

Magnetic field does not flow in direction of its source that is current; instead, it flows normal to the direction of current. Additionally, the magnetic force act perpendicular to magnetic field.

Direction of magnetic field can be detected using right hand thumb rule. According to right hand thumb rule; If a current carrying wire kept in hand, then direction of thumb implies direction of current and direction of fingers indicates direction of flow of magnetic field.

Example

If we take a bar magnet and bring it to an iron nail, at some point, the nail moves towards the magnet and sticks to it. Moreover, it remains there until we manually separate it from the magnet. So why does an iron nail stick to the magnet?

Reason behind is the force of attraction that connects the nail and magnet together. This force is applied by the magnet on the nail, and hence it’s called a magnetic force.

Here is one interesting question that I want you to answer; Is magnetic force is contact force, or in other words, is the contact between a magnet and nail necessary for the magnet to attract the nail?

When we move the magnet slowly towards the iron nail, and at this point, the nail also begins to move towards the magnet, it means the force came into action even when there was no contact between the magnet and nail. Hence, we can say that magnetic force is not a contact force.

What does this non-contact nature of magnetic force tell us

It tells us that there is an invisible field produced by the magnet in the space around it, and if you bring any ferromagnetic material in this field, then it experiences that force of attraction. We cannot see this field, but it exists.

Now one more interesting question, do you think that strength of this field is constant throughout the area around the magnet?

Let me explain it in easy way, suppose that there is a operating wireless fidelity router at some location. It provides us a signal altogether directions in some distance. currently so as to connect mobile to the net, we’d like to bring it to during this vary solely. This signal is stronger nearer the router.

“The nearer you bring your cellular phone to the router, the stronger the signal are”.

One can understand the magnet with same approach. magnet contains a field of force around it. The strength of this field is bigger nearer to the magnet and reduces as we tend to go more far away from it.

As you bring any ferromagnetic object during this field, it experiences an attractive force. The nearer we tend to bring that object to the magnet, the larger the force it’ll expertise till at some purpose once the force are massive enough to create the item leap towards the magnet.

Problems on magnetic field and magnetic force

Let us understand the relationship of magnetic field and magnetic force by solving some basic problems.

Problem 1

Find magnetic field exerted on a charge of 20 coulomb is moving perpendicular to the direction of magnetic field with velocity 2m/s and experiences a force of 5 newton.

Solution:

Given magnetic force, F_m

Velocity of charge particle, v

Magnetic field,

Strength of magnetic field is 0.125 Tesla.

Problem 2

Find magnetic force experienced by a charge particle with 50coulomb charge moving with unit velocity at right angle to magnetic field of strength 2 tesla.

Solution:

We know that equation of magnetic force and magnetic field is

So, force experienced by particle is 100 newtons.

Frequently asked questions | FAQs

Q. How magnetic field and magnetic force varies with each other?

Ans: “The magnetic force F is directly proportional to the strength of magnetic field.” As magnetic field gets stronger, magnetic force also increase and vice versa.

Q. At which point in magnetic field, the charge particle experiences strongest the magnetic force?

Ans: Magnetic field lines enter through south pole of magnet and leaves from north pole. Due to this magnetic force can be experienced strongest at either of the pole in comparison with opposite pole.

Q. Does magnetic field affect magnetic force?

Ans: Force experienced by moving charge is different at different points in magnetic field.

Magnetic forces of attraction or repulsion caused by movement of electrically charged particles is responsible for electric motor and attraction of iron towards magnet like effects. Static charges experience electric field whereas electric field and magnetic field can be experiences among moving charges. This magnetic force among two moving charges can be understand as the effect on either charge by a magnetic field by other.

Q. Why magnetic force is perpendicular to magnetic field?

Ans: If two objects or entities are at right angle with each other that means they are perpendicular to each other.

Because magnetic (Lorentz) field is directly proportional to v x B, where v is velocity of moving charge and B is magnetic field strength. As we know, vector cross product is always at right angles to each other of the vector factors, the force is perpendicular to v.

Q. Do magnetic force work?

Ans: Magnetic forces do not work.

For if Q moves an amount dl= vdt, the work done is

It happens because (B x v) is perpendicular to v, so (B x v).v= 0

“Magnetic forces may reverse the direction in which charges particle moves but cannot speed it up or slow it down.”

Also Read:

7 Harmonic Oscillator Examples:Exhaustive Insights and Facts

January 20, 2024November 17, 2021 by Keerthana Srikumar

Harmonic oscillator examples include even mechanical examples; some include electrical examples and system which executes simple harmonic motion.

Mentioned furthermore are a few harmonic oscillator examples:

Pendulum
Subwoofer
RLC Circuit
Mass-Spring System
Bungee Jumping
Cradle
Auditory Perception

Pendulum

The pendulum is a weight suspended from the point of axis for its free flow swinging sideways. When this pendulum is supplanted from its equilibrium position, it starts to oscillate sideways back and forth. The oscillation is regular and is in simple harmonic motion.

Any system that acts in simple harmonic motion comes under a harmonic oscillator. A simple harmonic oscillator is a type of harmonic oscillator. A system is said to be under simple harmonic oscillation when the restoring force is proportional to the displacement.

In a pendulum, the restoring force plays a vital role. The pendulum is sometimes called a pendulum bob. Now when the bob is displaced from its equilibrium position, it swings back and forth harmonically.

Restoring force acts on the pendulum so that the pendulum bob’s swing decreases slowly and the amplitude decreases. Another significant point to remember is that Hook’s Law attributes to this oscillation of the pendulum.

harmonic oscillator examples — “File:Foucault pendulum animated.gif” by DemonDeLuxe (Dominique Toussaint) is licensed under CC BY-SA 3.0

Subwoofer

A subwoofer is a device created to produce low pitch frequency. It has audio frequencies that are low based. The membrane in a subwoofer is said to make harmonic oscillations when the subwoofer delivers low audio frequency.

The subwoofer is a device that comes under a driven oscillator. The membrane in a subwoofer oscillates with constant amplitude producing a harmonic oscillation in the process. So this is an excellent harmonic oscillator example.

Inside a subwoofer is present a driver’s cone, which vibrates when it amplifies electric current into sound. This sound is nothing but the result of the back and forth harmonic oscillation. And the sound is the low base frequency with a low pitch.

We know the setup of a subwoofer and how it works, but we also need to know the presence of a driver’s cone. The driver’s cone is the mechanical part of any speaker system. This converts electrical energy into sound by creating an air space within. And this gives harmonic oscillations.

RLC Circuit

In an RLC circuit introduction of a resistor gives the harmonic oscillation as the LC combination does. This resistor reduces the oscillations in the circuit, therefore, producing low base frequency and decreasing the peak resonant frequency.

The resistor added in an RLC circuit reduces the harmonic oscillations. And this is known as damping. Damping is the one that reduces the oscillations, letting it decay. So for an RLC circuit to act appropriately as a harmonic oscillator, the resistor should be added in parallel and series.

So, in parallel resistor should be added in such a way so that the oscillations do not decay. And in series resistor must be added in small so that the resistance in the circuits is made as small as possible, so the damping doesn’t affect the oscillations.

By changing the resistance according to or equivalently by deciding the damping factor by changing the resistance in a circuit, issues such as dielectric loss in coils and capacitors can be brought up and solved.

Basically, in an RLC oscillator, two types of oscillators come into play, the mechanical oscillator, and the electrical oscillator. One of the main features of the RLC circuit is that it decays even during oscillations. The driven oscillator provides a sinusoidal signal through harmonic oscillations resulting in a sine wave instead of a square wave.

Mass-Spring System

A mass-spring is the system where two more masses are suspended from a rigid support. And the oscillations of the mass from its equilibrium position back and forth are evaluated.

For example, let us consider two springs having two masses, each suspended from the rigid support. The spring constant for both springs would be the same, but the mass may differ. When a mass weighing lighter than the other mass weighs more is suspended, the period of oscillations varies.

Smaller mass will oscillate harmonically less than the mass that is larger than the less suspended mass. The configuration of the masses can be explained by the general coordinates of the two systems.

This is done by considering how far the systems oscillate from their equilibrium position back and forth, finally coming to rest due to the restoring force acting upon them naturally.

The mass-spring system is generally used in equipment where the vibrating part is set apart from the supporting element. For example, in a lightweight roof system, this mass-spring concept is put in to separate it from any loud equipment that is under high vibrations.

mass spring faster — “File:Animated-mass-spring-faster.gif” by Svjo is licensed under CC BY-SA 3.0

Bungee Jumping

Bungee jumping is an excellent harmonic oscillation example. Also, this exhibits the simple harmonic oscillations in a better way. The up and down oscillations of the bungee cord from its equilibrium position explains clearly the simple harmonic oscillations present in the system.

The basic concept of harmonic oscillation in bungee jumping is that the oscillation occurs after the free fall of the jumper. The jumper is tied to the bungee cord, which moves up and down from the equilibrium position. The weight to be suspended in the cord is in accordance with the length of the cord. In this way, Hooke’s Law (F=kx) is obeyed.

The jumper experiences a free-fall, after which harmonic oscillation comes to action. The jumper moves up and down, which happens when the bungee cord oscillates to and forth from the equilibrium position.

Cradle

Cradle exhibits the simple harmonic motion in play. A single push given to the cradle makes it oscillate to and fro from its equilibrium position.

When the cradle is given even a slight push, it oscillates from equilibrium position back and forth. And this comes to rest when the oscillations decrease, making the amplitude smaller. The to and fro motion is period and is said to have simple harmonic oscillations.

Auditory Perception

Auditory perception is also known as the sense of hearing in human beings. This process is carried out when sound waves enter the eardrum causing the vibrations to and fro, and finally, the sound is heard by our human ear.

The sound waves travel through the membrane of the ear canal, oscillating back and forth in periodic motion. This is called simple harmonic motion (oscillation). Both the eardrums oscillate back and forth for four cycles and are associated with the movement of the eyes.

human ear — “Ear” by naikalieva is licensed under CC BY-SA 2.0

These above mentioned examples help us understand the concept of harmonic oscillations in a better way.

Also Read:

Critical Damping Applications:Detailed insights

January 21, 2024November 10, 2021 by Keerthana Srikumar

Critical damping applications are one of the primary forms of bringing an oscillating system to rest. Essential plates of damping are used to get the vibrations of the system to complete rest.

Given below are a few critical damping applications that are found in daily life. Critical damping are very useful for such daily-life activities.

Friction Damping Plates
Electric Circuit Damping
Hydraulic Recoil Machine
Door-closing Mechanism
Speedometer
Automobile Shock Absorber

Friction Damping Plates

Friction damping plates are the devices that reduce the excessive vibrations in a system, thus converting kinetic energy into thermal energy through friction. The concept of critical damping comes into action here.

This brings the massive vibrations to the equilibrium position as quickly as possible. Therefore the friction damping plates are primarily used in building to dissipate seismic energy by which the building can withstand an earthquake.

The concept is, when a building encounters an earthquake, the plates underground change places but the friction damping plates make sure plates under the construction come back to the rest position, causing less destruction. In this way, critical damping applications find their uses.

Electric Circuit Damping

A primary RLC circuit is known as an electrical circuit. R means resistor, L means inductor, and C implies capacitor.

In this circuit, an inductor (L) stores the energy in a magnetic field when the electric current flows through the circuit; a capacitor (C) stores electric charges, which is why the electric current passes. But a resistor (R) breaks the current flow in a system similar to the damping in oscillating systems.

Here the addition of a resistor in an electric circuit decays the oscillations of the circuit when connected in parallel.

The resistor reduces the peak resonant frequency in the circuit. Critical damping is one of the primary reasons for reducing frequency due to the arising from the LC combination in the RLC circuit.

Hydraulic Recoil Mechanism

When a firearm fitted with hydraulic recoil, it reduces the effects of recoil in the gun and provides accuracy. The hydraulic recoil fixed in the barrel, so when the gun is fired, the recoil energy caused by the projectile makes the barrel go backward and locked in the bolt.

Basically, a barrel and the bold are together, soon after firing next step is that the barrel and bold travel backward till the end of the gun and come forward with some force so that the bold is firm, filling the next cartridge. In contrast, the barrel goes forwards and pushes the current cartridge to be fired.

This phenomenon occurs because the critical damping is present; this helps the barrel return to the rest position as quickly as possible to fire the next one.

Door-closing Mechanism

Adding a door damper (critically damped) reduces the damage to the door system as a whole.

Generally, when a door opens and closes, it makes noise, and damage occurs to the doorframe and such. So when a damper attaches to the door, it reduces the door from slamming and causing destruction.

Once the door opens, it suddenly comes back to its original position with no further delay and also has no adverse effect on the system. Critical damping helps the system from further damage or so.

Speedometer

Speedometers are critically damped instruments so that when the vehicle accelerates, it does not oscillate and create disturbances during riding or driving.

In the speedometer, the needle that indicates the speed does not constantly oscillate and confuses the person handling the vehicle.

Since the speedometer is critically damped, it does not have a constant oscillation; once the vehicle is accelerated, it does not oscillate at all and stays in that stable position unless the velocity is changed, which changes the acceleration.

Automobile Shock Absorber

Shock absorbers are a spring present in cars that dissipate the energy created from an abrupt movement while the car goes through a rough patch. This spring smoothens the entire ride of the vehicle.

The spring, also called a shock absorber, absorbs part of the abrupt movement in the form of energy during the ride, which dissipates the energy.

As this is a continuous process, the spring has to do this as quickly as possible, so the car goes up and down. The shock absorber returns to its original place and controls the process as well.

What is critical damping resistance

Critical damping resistance is the resistance of a critically damped electric circuit and ceases the oscillations.

An RLC circuit is the best suited to determine the resistance of a critically damped circuit. R is the resistor, L is the inductor, and C is the capacitor. The LC combination is the reason behind the oscillations of the system. R-value affects the damping of the whole system.

When R is small or large, it means the circuit is either underdamped or overdamped. When the circuit is underdamped, ringing happens that is the function of the circuit occurs. Here it is ringing, but in the other circuits, it can be ringing and any other application.

When R is made small, it reduces the frequency due to the oscillation in the system. Resistance is the one that breaks the flow of electric current, hence in a circuit, the resistance and cuts down the peaks of the resonant frequency.

The critical damping resistance can also be explained as the required resistance to stop the oscillations and bring them back to the equilibrium position.

How to find critical damping resistance

Critical damping resistance is calculated using the damping factor. This formula is used to find the critical damping resistance.

For a critically damped circuit(R LC in parallel), the resistance can be found using the formula: ζ = R/2 (C/L)^1/2. Zeta (ζ) is the damping factor and for critical damping (ζ) is 1.

Let us understand using a numerical problem. Calculate the critical damping resistance in the given circuit.

ζ = R/2 (C/L)^1/2

1= R/2 (64/16)^1/2

1= R/2 x 4

R = 0.5 Ω

Critical damping condition

The condition for the critical damping is that the damping factor should be equal to 1. That is Zeta (ζ) = 1.

In a system, the oscillations will completely decay; that is, it will stop and come back to the rest state, the equilibrium position, called critical damping.

The minimum amount of force or resistance (based on which system we are working on) required to stop the system under motion to bring it back to the equilibrium system is critical damping.

The condition for a critically damped system directly depends on the damping factor. And the requirement for critical damping is that the damping factor should always be equal to 1.

The one primary condition for critical damping is that the oscillations must come to a stop without going back and forth and returning to the equilibrium position as quickly as possible.

When Does A Physical Change Occur: Detailed Analysis

January 20, 2024November 8, 2021 by Rabiya Khalid

The changes happening around us are either chemical or physical changes. Let’s have knowledge about when does a physical change occur.

Physical changes occur when the substance undergoes a transition in the physical properties. Any change in the state, shape, color, or size of the object is said to be a physical change. They are generally known as temporary changes. The physical change can either be reversible or irreversible.

A physical change arises due to changing physical properties, i.e., size, shape or state, etc. Generally, physical change is caused by applying force or energy to the object. During a physical change, the total internal energy before and after the reaction or change remains the same. This means that the bonds of the object or substance remain intact. It does not break to form a new substance.

Let us understand a common example of physical change that is the melting of butter or vice versa. For melting butter, energy is required. Now this energy should be sufficient enough to change the state of the butter and does not break the bonds. When the butter acquires this energy, its molecules gain energy and come in rapid motion. Due to this, they only get apart and change into a liquid state. And hence physical change occurs.

buttered 18641 1280 — Image Credit: https://pixabay.com/photos/buttered-toast-food-bread-18641/

This change can be reversed, and butter can regain its original state on freezing, thus leading to phase change. Now physical change can also occur by changes in size, shape, odor, color, temperature, or pressure. Now when you break a pencil into two halves, its shape and size both get changed, and hence physical change has occurred.

Image Credit: Andy Schmitz, Sodium chloride dissolution, CC BY 3.0

Let’s take another case of sugar dissolving into the water. Now, this is a common example of reversible physical change. Many a time, it is confused to be a chemical change. For this, let us see how a physical change occurs. On dissolving sugar into water, no new substance is formed with no chemical reaction. During the process, the thing that happens is the change in form. The identity of both the solute and solvent remains the same. Here the water that is our solvent gets its molecules further apart, and sugar molecules fill that space. Hence this process occurs.

Now it is easy to reverse back the process and generate sugar back from the solution. The vaporization process, along with condensation and crystallization, will bring back the molecule. Hence now we know when does a physical change occur.

Frequently Asked Questions (FAQs)

Name two types of changes that can occur.

There are two types of changes that are known to humans; chemical change and physical change.

The change that forms a new substance by altering the chemical composition of the substance is said to be a chemical change. All the modifications that happen in the physical characters are inferred as physical change. There is no formation of new substances during the physical change.

Explain the physical change.

The changes happening about the physical properties of the object, substance, or compound is said to be physical change.

It involves changes in size, shape, color, odor, temperature, or pressure. Physical changes are said to be temporary changes. They can be reversed to bring back to the primary state, and some are irreversible too. E.g.:- broken glass, tearing paper, chopping vegetables.

When does a physical change occur?

Physical changes can be reversed or stay irreversible depending upon the situation.

A physical change occurs when there is any kind of alteration in the physical properties of the object. The changes can be just temporary or become irreversible. These changes do not lead to the formation of any new substance.

Is physical change temporary or permanent change?

Physical changes can be reversed back to their initial state by physical means.

Since physical change can be reversed, it is said to be a temporary change. The chemical change is known to be a permanent change. But remember, not all physical changes are reversible, like cutting trees into logs.

How to know the physical change has taken place?

Since the physical change brings changes in the physical properties of the substance, it can easily be seen.

If you see a change in any physical characteristics of the object, know that physical change has taken place. For example, when you drop a glass, it breaks into smaller pieces. The size and shape get deformed on hitting the floor. Hence physical change has occurred.

What are the signs of physical changes?

The change in physical properties is classified as physical change.

The signs of physical change are shape, size, color, matter, odor, temperature, and pressure. Any change in the following properties indicates that the physical change has taken place. These changes can clearly be observed by us and in the most cases are reversible.

Also Read:

Resultant Force And Equilibrant Force:Exhaustive Comparison

January 1, 2024November 4, 2021 by Keerthana Srikumar

Resultant force is one single force replaced by multiple forces and equilibrium force is the balanced force where the net force acting is zero that is direct opposite to resultant force. Hence this is basic difference between resultant force and equilibrant force.

Resultant force is the sum of all individual forces acting on a body by vector determination. Resultant force can be zero if one force is opposite to the other combination. There are several forces acting on a body and they are dealt separately in terms of vertical and horizontal forces.

When the magnitude is the same and directions are opposites the forces cancel out each other we get a value of force which is the resultant force. For instance, 5N force on the left and 9N force on the right gives resultant force as 4N.

Resultant force examples

Let us have four forces acting on a system at the same time, 60N, 70N, 40N, -20N. The force 20N is negative because it is acting on the opposite direction to that of the others. Evaluate the resultant force.

F_R = f1 + f2 + f3 + f4

F_R = 60N + 70N + 40N – 20N

F_R = 150N

Let two forces act perpendicular to each other, 9N and 4N. Determine the resultant force.

The formula for resultant force acting perpendicular to each other is

F = [(F1)² + (F2)²]^1/2

F = [(9)² + (4)²]^1/2

The resultant force or any other type of force can be explained easily using a free-body diagram. In this diagram we use arrows to indicate the magnitude and direction of the forces acting. The arrows pointing to a direction is the path of the force followed, and the length of the arrow shows specifies the magnitude.

While calculating the force present in the body, several forces come into play but resultant force gives value for the entire force present. Multiple forces acting on them goes balanced and unbalanced.

When the individual force have the same magnitude as the other they sum up also when the direction is the same then the system is said to have unbalanced force. But when the magnitude is the same and the direction is opposite to each other they cancel out each other and the system is said to have balanced force.

In a system there are several possible forces acting namely, normal force, frictional force, tensional force, gravitational force and so on. Resultant force is the final value of adding up these forces acting upon a body.

Equilibrant Force Concept

When the magnitude and the direction of the force acting on a body are balanced, showing zero net force and zero torque present in the system is known as the equilibrant force.

The state of balanced force occurs when a system in equilibrium. This happens when different forces acting upon the object are considered to be balanced.

The balancing of force in a system occurs when leftward force balances the rightward force and upward force balances the downward force.

Generally when the system is said to have balanced force, the individual forces cannot have the same value. For example, when a body is said to have balanced force, the individual force may differ and is explained using a free-body diagram.

Let’s consider a simple experiment to understand the concept of equilibrium force.

In physics lab, an object is suspended by two or more strings; force exerted is measured at angles made by the string with the object. Now the total number of forces acting on the object is measured.

If the object was to be in equilibrium the net force acting on the object should be of 0N. also, by adding up the force should be equal to zero.

Equilibrium Force Examples

Consider a man standing on the ground motionless. The forces acting on him will be zero since there is no acceleration and velocity. Due to this the man is said to be in static equilibrium.

Since the number of forces acting on the man is zero, and then the condition calls for equilibrium force in existence.

A car moves on a highway with constant acceleration and velocity. When it does not move the whole system stays motionless. The forces acting on the system is in each direction.

When children are seated on a see-saw, a rotating system, are said to be in equilibrium. If they are motionless and the forces acting on them becomes zero, by this way the torque becomes zero and it gives way for equilibrium force.

Therefore by all means, the total number of forces acting upon a body is balanced, making the net force zero, and the equilibrium force is achieved.

And when the entire force acting upon the object its magnitude and direction values are taken into account, by which on adding the resultant force is obtained.

Frequently asked Questions

Why does a force in equilibrium be zero?

In this condition two equal and opposite force exists balancing each other and the acceleration becomes zero.

The word equilibrium simply means balancing. In order for a system to be in equilibrium, there must be a balance of all the forces in the system and net force becomes zero.

When a net force does becomes zero in an equilibrium system?

The net force in a system becomes zero when all the forces acting in the system is balanced and when the acceleration turns to be zero.

This process occurs when all the forces in a system is balanced from all directions. Acceleration being zero the torque acting in a rotating system also becomes zero.

Will torque become zero if the net force is zero?

Torque is a cross product of distance and force, so when the net force is zero, torque will be zero.

If the displacement appears right after applying the force then the torque will be bigger than force. If displacement is missing even after the force application then force will be zero as well as the torque.

What is dynamic equilibrium?

Dynamic equilibrium is state of a system with motion and net force not equal to zero.

Dynamic equilibrium differs from static because dynamic mean the body is in motion with changing velocity and acceleration. The constant change in the acceleration velocity and torque (in rotating systems), is dynamic equilibrium.

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Do Humans Have Animal Cells: Interesting FACTS

January 20, 2024November 4, 2021 by Trisha Dey

Humans are composed of animal cells but only of a single specific type.

Scientifically, animal cells are the structural and functional units or essentially the building bricks of all organisms that belong to Kingdom Animalia.

They can specify and form any required tissue, organ or organism based on the genomic components.

Animal cells are eukaryotic cells(i.e cells containing a defined nucleus), surrounded only by a plasma membrane, unlike plant cells which are enclosed by both cell membrane and cell wall. The absence of the cell wall means the cells do not have a rigid or specific shape. But in contrast, this allows the cells to have different shapes and form different tissues, organs and organ systems.

Human cells are just the specific animal cells that make up humans, for ultimately they are animals as well.

Components of an animal cell:

Generally smaller than plant cells with an irregular shape due to the absence of the cell wall animal cells still come in a variety of sizes based on the organism. But similar to plant cells they have all the other major organelles characteristic of eukaryotes.

do-humans-have-animal-cell — So do humans have animal cells?

Kingdom Animalia begins from Sponges and ends at Mammalia with humans or Homo sapiens sapiens being the most advanced. With the evolution and advancement of the organisms, there is advancement in their cellular complexity, but the main components remain the same.

Cell membrane or the thin covering that protects cells(the thin while layer that we often peel off boiled eggs). The cell membrane allows the cell to exchange gases and also communicate with adjacent cells.
Nucleus and a nuclear membrane- as animal cells are eukaryotic this means the genetic material is present in a condensed form in a specific organelle i.e. the nucleus instead of floating around in the cell. The nucleus has a nuclear membrane to protect it and also the membrane itself has more important functions in protein synthesis and cell transport.
Endoplasmic Reticulum or simply the ER is a continuation of the nuclear membrane. They mainly function in synthesizing lipids(fatty substances).
Mitochondria These organelles are what ultimately break down molecules to release energy. Hence they are called the batteries or powerhouse of the cell.
Golgi Apparatus and Ribosomes: The ribosomes main function is to synthesize proteins that are received by the Golgi apparatus. They receive them along with lipids from the Endoplasmic Reticulum after which they are transported to their target sites.
Lysosomes are cell cleaners. They are enzyme filled packets that dispose of or recycle any material that is unwanted in the cell.
Ribosomes are simply the protein synthesis centres. These are small organelles that are often stuck to the nuclear membrane and the ER.
Vacuoles are empty pockets that can beused for storing water, waste products or even food by the cell.

Most common types of animal cells:

These include the most common animal cell types that occur most frequently throughout the animal kingdom. These include

Skin Cells: They occur in all animalsand may have more than one layer called the dermis.
Muscle cells: Animal are distinguished by their ability to move. Except in the case of unicellular or sedentary (those that do not move)organisms, most animals have muscle cells to help in movement. They also make up
some important organs like the heart.
Blood cells or corpuscles are the cellular components present in most animal vascular systems.
Nerve cells Animal having even the simplest nervous systems have a collection of nerve cells which may just form a ganglion.
Fat cells Most animals use fat cells present to store food materials for hibernation or morphing.

Some specialized animal cells present in lower animals:

Choanocyte: Specialised cells in sponges have a flagellum that helps to control the movement and flow of water throughout the cavity of the organism.
Cnidocytes: Found in cnidarian like jellyfish and hydra these cells are also called stinging cells. They contain organelles called nematocysts – consisting of a coiled thread occasionally with barbs. These cells allow the animal to sting and immobilize prey with poison. (Box jellyfish are one of the most venomous animals in the world)
Flame Cells: Found specifically in phylum Ctenophora or simply what we call flatworms(most intestinal parasites belong to this category). Since they are not developed flame cells in these animals act as kidneys to filter toxins and waste from the circulating fluid.

How many animal cells does a human have?

Technically speaking humans have only one type of cell i.e the human genomic cell.

Humans are the most complex organism created in nature, consisting of trillions of cells. But they all have the same genomic constituency containing 3 million base pairs. All the cells are grouped according to function and organs. But they are all the same type of animal cell i.e. a human cell.

Though the cell genomic content is the same the all the cells do not have the same structure or function.

The cells have been differentiated in foetal form and they form different tissues, organs and organ systems.

Neurons: Or nerve cells is the basic unit of the nervous system that controls all bodily functions in the body. These cells carry messages from the brain to all the organs and muscles with the help of small electro-chemical signals.
Muscle Cells: Comprising of three types(smooth, cardiac and skeletal) these cells form muscles that make movement possible. Cardiac muscles form the heart and its walls, which allows it to rapidly pump blood.It is because these cells are made up of fibres that allow contraction.
Red Blood Cells: Making up the corpuscular part of blood, these cells have a biconcave discoid shape. The main function of RBCs is to transport oxygen and carbon dioxide to and fro from the lungs. For this purpose, RBCs have an iron component called Haemoglobin that turns red on binding with oxygen giving the red colour; hence the name.
Leucocytes: Typically called White Blood Cells or WBCs, they make up the immune system in humans. Found in both the blood and the lymphatic system, these cells help us fight against infectious diseases and foreign particles(like allergens).

They are further divided into:

Neutrophils
Eosinophils
Basophils
Monocyte
Lymphocytes

Lymphocytes can also be of 3 types– T Cells, B cells and Natural Killer Cells.

Nephrons: These are specialized cells that are found in Kidneys. They look like a sieve with a large tube and remove the excess salts, waster products and unnecessary materials from the blood.

do-hmans-have animal-cells — A human nephron
Image credit: Wikimedia

Do all living things have animal cells?

Animal cells are specific to Kingdom Animalia.

All animals ranging from sponges to mammals are composed of animal cells. These cells can form a simple organism or can form tissues, organs and systems i.e more complex. Some cells may be specifically produced by a certain animal to adapt to its environment.

So animal cells in scientific terms are limited to animals only. Plant cells that make up the major portion of the Earth’s biomass are vastly different in composition. The most important difference is the presence of cell walls and chlorophyll or other pigment-containing organelles. Cell walls made up of polysaccharides are present in all organisms that we consider plants- even unicellular yeast. The cell wall is what gives plant cells their rigidity and the ability to last through a long time(the very reason wood furniture is so long-lasting).

The second biggest difference is the presence of chlorophyll. This is a pigment found in a plant-specific organelle called – CHLOROPLAST. This pigment allows plants to photosynthesize i.e to produce their food in the form of simple sugar(hence the name Autotrophs). Chlorophyll uses light energy as a catalyst and converts atmospheric Carbon Dioxide and water to Glucose and oxygen.

choloroplast — Structure of a chloroplast
Image credit: Wikimedia

What do animal cells have that humans don’t?

Conditionally as humans are animals, they do not contain an excess or deficit in organelles when compared to a normal animal cell.

Humans are considered as higher beings but being classified in kingdom Animalia means they are animals. Under a microscope, a cell taken from a random animal and one taken from human tissue will not have much difference. This characteristic is what allows scientists to discover how closely one animal species or genus is related to another.

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