In this article, we shall learn about the negative electrostatic force, what makes the electrostatic force negative, with detailed facts.
The electrostatic force is a force imposed on other charged particles due to the presence of that charge in the electric field produced by the electric charge in that area.
What is Negative Electrostatic Force?
The electrostatic force is given by the equation F=1/4 ɛπ (q1q2/r2)
Where 1/4 ɛπ=9*109Nm2/C2 is a constant.
ɛ0=8.85*10-12C2/Nm2
q1 and q2 are two charged particles, and
d is a distance between the two charges
If the product of the two charges is negative then the electrostatic force between the two charges is negative, hence the force is said to be a negative electrostatic force.
Problem 1: Calculate the electrostatic force between the charge q1 and q2 possessing charge -1C and +3C respectively. These two charges are separated by a distance of 2.5 cm.
Given: q1= -1C q2= +3C d= 2.5cm
We have, F=1/4 ɛπ (q1q2/r2)
=9*109 * {(-1C)* 3C/(2.5)2}
=9*109*{-3/6.25}
=-4.32*109N
The electrostatic force is negative due to the negative charge of the particle.
Read more on Electrostatic Force And Charge: What, How And Detailed Facts.
When Electrostatic Force is Negative?
The force between the two oppositely charged particles is always attractive.
If the two charged particles separated by some distance shows the force of attraction towards each other then the electrostatic force is negative.
The electrostatic force is F∝ q1q2 and F∝ 1/d.
The distance cannot be negative; hence, the condition for the electrostatic force to be negative completely relies upon the product of the two charges among which the electrostatic force is imposed.
If one charge is positive the other must be negatively charged. That is if q1=+ve then q2=-ve; and if q1=-ve then q2=+ve.
Both the charges should not have unique charges. If the charges are like charges then the product of the two will be positive. That is if q1=+ve and q2=+ve; then q1 q2=+ve and if q1=-ve and q2=-ve, then q1 q2=+ve. Hence, both the charges should not have similar charges for the electrostatic force to be negative.
Read more on Electrostatic Force And Distance: What, When, How And Detailed Facts.
Negative Electrostatic Force Point
The negative electrostatic force is due to the negative charge carriers that produce negative electric fields. The force on the positively charged particle present in this negative electric field is a negative electrostatic force and the point of origin of the negative electrostatic force that is the point charge which is negatively charged generating the electric field resembles the negative electrostatic force point.
The positive charge in the electric field produced by the negative point charge will show the forces of attraction towards the point charge; hence the electrostatic force will be negative. All the other negative charges in this field area will repel away from each exerting positive electrostatic force on negative charges.
Read more on The Electric Field Between Two Plates: Formula, Magnitude, Direction, Imp FAQs.
Can Electrostatic Force be Negative?
Basically, if we see, the presence of force implies the positive quantity of force, so the force can be either zero in the absence or positive.
But the electrostatic force is a vector quantity and can be negative depending upon the charge of the particle imposing force on the other charges.
Every charged particle produced an electric field in proportionate with the charge that they carry, given by the relation
E=1/4 ɛπ (q/r2)
The electric field is related to the electrostatic force between the two charged particle by the relation,
F= qE
Where F is an electrostatic force
Q is a charge and
E is the electric field
The electrostatic force will be negative, if the positively charged carriers are present in the electric field generated by the negative charge, or if the negative charge is present in the field produced by positively charged particles.
The negative electrostatic force indicates that the force acting between the two charged particles is the attractive force. If the electric field is positive, then the electrostatic force imposed on the negative charge in this field will be negative.
Read more on Is electrostatic force conservative: Exhaustive insights.
Let us understand this with an example.
Consider a charge particle present at a point A as shown in the below figure. The electric field produced by this particle is 14 × 1022 N/C. Two other particles q1 and q2 having charge of -2C and +2C are placed in this field region separated by some distance. Calculate the electrostatic force imposed on each of these charged particles due to the electric field produced by a particle at point A.
Given: E =14 × 1022 N/C, q1 = -2C, q2 = +2C
We know F=qE
Hence, the electrostatic force on charge q1 in electric field is
F1=q1E
=(-2)*14*1022
=-28*1022N
The electrostatic force is negative; this implies that the force between the charge q1 and the source point charge is attractive. The charge at point A is exerting a force on q1 to bring it closer to point A.
The electrostatic force on charge q2 in electric field is
F2=q2E
=(2)*14*1022
=28*1022N
The electrostatic force between the charge place at point A and the charge q2 is positive, which indicates that the force between the two is repulsive as they constitute similar charges.
Read more on Net Electrostatic Force: How to Find, Problems and FAQs.
Negative vs Positive Electrostatic Force
The negative electrostatic force is an attractive force existing between the two unlike charges whereas the positive electrostatic force is a repulsive force between the two like charges, that says, both the charges are either positively charged or negatively charged.
The negative electrostatic force increases if the distance separating the two charges increases apart and the positive electrostatic force increases if the distance separating the two charges decreases.
Read more on Electrostatics.
Frequently Asked Questions
Is the work done by the negative electrostatic force?
The negative electrostatic force is an attractive force exerted on each by two unlike charges.
The work is done by the particles on each other to get them closer to each other, hence exerting the force of attraction.
Is negative electrostatic force an attractive force?
The negative electrostatic force resembles the attractive force between the unlike charges.
The unlike charged particles always tend to attract towards each other as the empty holes that give a positive charge to the particles due to lack of electrons are ready to fill this vacancy by attracting electrons.
Also Read:
- Torsion force example
- Does the direction of magnetic force change
- Force on moving charge in electric field
- Is electrostatic force conservative
- Is gravitational force a contact force
- Is magnetic flux a magnetic force
- Centripetal force vs centripetal acceleration
- Electrostatic force and charge
- Is gravitational force a central force
- Electrostatic force and distance
Hi, I’m Akshita Mapari. I have done M.Sc. in Physics. I have worked on projects like Numerical modeling of winds and waves during cyclone, Physics of toys and mechanized thrill machines in amusement park based on Classical Mechanics. I have pursued a course on Arduino and have accomplished some mini projects on Arduino UNO. I always like to explore new zones in the field of science. I personally believe that learning is more enthusiastic when learnt with creativity. Apart from this, I like to read, travel, strumming on guitar, identifying rocks and strata, photography and playing chess.