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The kinetic friction depends upon-

The kinetic friction depends upon- Correct Answer Nature and material of the surfaces in contact

CONCEPT:

  • Frictional force: It is a type of contact force.
  • Contact forces: It arises when two bodies are in contact with some other object: solid or liquid
    • When two bodies are in contact mutual force arise due to newton's third law of motion.
    • The component of contact force normal to the surface is called normal reaction and the component parallel to the surface is called friction.
  • Kinetic friction: The frictional force that opposes the relative motion of two surfaces in contact.

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  • If fk is the kinetic friction, μk the coefficient of kinetic friction, and N is the normal reaction force, the law of kinetic friction may be written as:

⇒ fk = μkN

EXPLANATION:

  • Kinetic friction depends upon the nature and material of the surfaces in contact.

It is independent of:

  1. Area of contact between two surfaces.
  2. The shape of the surface in contact.
  3. The relative velocity between the two surfaces provided the relative velocity is neither too large nor too small.
  • Hence option 4) is correct.

Related Questions

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Consider the following statements: Kinetic friction is the frictional force that opposes the motion of two surfaces in contact. The static friction is independent of the area of contact. The kinetic friction depends upon the area of contact.  fs = μsN always. Which of the above statements are correct.
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If the amplitude or oscillation of a simple pendulum is very small, then its time period of oscillation
1. depends on the length of the pendulum, L.
2. depends on the acceleration due to gravity, g.
3. depends upon the mass of the bob of the pendulum, m.
4. does not depend upon the amplitude of the pendulum, A.
Select the correct answer:
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Which of the following is correct? I. Sliding friction is smaller than static friction. II. Rolling friction is smaller than sliding friction.