Kinetic Friction vs Kinetic Force:Detailed Analysis


The kinetic friction and the kinetic force seem like the same quantity, but they are not the same.

Though Kinetic friction and kinetic force are both exerted on the moving objects, let us study the facts which make these two physical quantities differ by analyzing Kinetic friction vs Kinetic force in this post.

Comparison between the Kinetic Friction vs Kinetic Force

 The below table may help you to understand the nature and behavior of kinetic friction vs kinetic force.

Kinetic frictionKinetic force
Kinetic energy
Kinetic friction reduces the kinetic energy of the system. This loss of kinetic energy results in releasing heat energy.
Since the kinetic force makes the body accelerate more, the kinetic energy increases with increased acceleration.
Nature of the surfaceThe Kinetic friction constantly evolved between the two solid rough surfaces. The surface must be rough. It may be flat or inclined.The kinetic force is exerted only in the inclined plane because in an inclined plane to move upward it takes more force for the motion. Since on the flat surface, the body does not require any force to keep on moving. So that on a flat surface, the acceleration is constant.
GravityThe influence of gravity on kinetic friction is constant as kinetic friction is independent of gravity. Still, the factor involved in the kinetic friction, i.e., the normal force, is influenced by the acceleration due to gravity.Kinetic force is primarily influenced by gravity. The object accelerates rapidly down the ramp because the gravitational pull-down ramp is more.
Net weightThe net weight of the object gives the normal force acting on the body, which is responsible for the kinetic friction.The kinetic force is itself considered as a portion of the possible net weight of the object.
CoefficientsThe ratio of kinetic friction and the perpendicular reaction gives the coefficient of kinetic friction. This is a dimensionless quantity which exerts wide influence over the kinetic friction.The coefficient kinetic force is the wrong terminology to explain the force. Since all the coefficients are dimensionless, quantity is used to express the nature of the physical quantity. But in the case of kinetic friction, it is an irrelevant quantity.
DirectionKinetic friction always acts in the opposite direction to the relative motion of the objects.Kinetic force acting on the moving body is in the direction of the relative motion of the body.
The study of kinetic friction vs kinetic force convinces us how the two forces exerted on the moving body differ from one another.

Definition of kinetic friction and kinetic force

In order to understand the action of kinetic friction vs kinetic force on the object, the definition of them is very helpful.

Kinetic friction is the resistance offered to the moving body to restrict its motion. In contrast, the Kinetic force is probably a net force that is exerted on the object parallel to the plane of inclination that causes the object to accelerate.

kinetic friction vs kinetic force
Kinetic friction vs kinetic force

By the above definition, it is clear that the kinetic friction stops the moving object and the kinetic friction allows the moving object to accelerate more.

Interesting facts to remember

  • When the body moves down the hill, the kinetic force is maximum, moving rapidly. As it moves near the flat surface, the kinetic force becomes minimum, and in some instances, its motion is retarded by the kinetic friction.
  • Both kinetic friction and kinetic force are applied to the types of forces exerted on the body; these are equal and opposite to each other.
  • It is impossible to stand up if the friction acting between our body and the surface is absent.
  • Wheels are used to reduce friction and accelerate rapidly, but the wheel couldn’t work properly without friction.
  • In the case of both kinetic friction and kinetic force, the energy may get lost by releasing some amount of heat.
  • The kinetic friction always retards the kinetic force.
  • In some sense, kinetic force is an uncommon usage term. Kinetic force is considered as the impulsive force which arises due to collision. It is referred to as the contact force and given by Newton’s laws of motion as, Impulse = Ft
  • Kinetic friction is the one responsible for the object’s motion, while kinetic force increases the speed of the movement.

Frequently asked questions

Does the kinetic friction remain constant throughout the motion?

 When the applied force is maximum, and overcomes the stiction, then the kinetic friction evolves.

The kinetic friction remains constant until the body gains the energy to move when the kinetic energy is lost in the form of heat and reaches the threshold motion, the kinetic friction increases.

Does the increase in speed increase the kinetic friction?

No, the increase or decrease in the speed does not alter the kinetic friction at the moderate level.

The kinetic friction always increases when the normal force between the objects increases. When the speed is increased slightly, the kinetic friction remains constant. If the speed is increased to the greater value, the friction offered by the surface becomes negligible.

How does the kinetic energy increase with the kinetic force?

Kinetic force makes the object accelerate more; this helps the energy to exert more on the body.

When the speed of the body increases, the body requires more energy to keep the force steady, the distance traveled by the body increases at a constant force as the force keeps on increasing the kinetic energy increases too.

What is the major application of kinetic friction?

The kinetic friction is mainly applicable in lubrication.

The wear and tear of the machinery depends on the kinetic friction. The car brakes use the principle of kinetic friction, which indeed uses lubrication.

How does kinetic friction be responsible for the motion?

The kinetic friction converts the kinetic energy into heat energy.

When the two surfaces are in contact, and when the force is applied to one surface, it begins to move. The kinetic energy is converted into heat only when the surface of one block slides over another surface. This energy is sufficient to cause motion.

Does the mechanical energy is conserved in the kinetic friction?

Since the kinetic friction reduces the mechanical energy of the system, it is considered non-conservative.

If the total sum of potential energy and the kinetic energy is constant then the energy is said to conserved. In the case of kinetic friction, the energy conversion between the potential and the kinetic energy does not occur. Hence the mechanical energy is not conserved.

How does the kinetic energy equal to the kinetic friction?

The kinetic friction and kinetic energy are not related to one another. Both are different components.

Kinetic energy is the energy correlated to the body in motion. This energy may get reduced if the friction exerted on the body is more. But kinetic energy and the kinetic friction are unequal quantities.

Keerthi Murthi

I am Keerthi K Murthy, I have completed post graduation in Physics, with the specialization in the field of solid state physics. I have always consider physics as a fundamental subject which is connected to our daily life. Being a science student I enjoy exploring new things in physics. As a writer my goal is to reach the readers with the simplified manner through my articles. Reach me – keerthikmurthy24@gmail.com

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