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Limiting force of friction is defined as the frictional force which exists when a body

Limiting force of friction is defined as the frictional force which exists when a body Correct Answer just begins to slide over the surface

Explanation:

  • As the force is applied to the body the friction force acts on the body which will be opposite to the applied force.
  • As the value of P is going on increasing, at some stage the solid body will be on the verge of motion. 
  • The friction force corresponding to this stage is called the limiting force of friction.

Important Points

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Law of limiting friction for dry surfaces:

  • When two bodies are in contact, the direction of the force of friction on one of them is opposite to the direction in which this body has the tendency to move
  • The frictional force is independent of the area of contact of the surfaces
  • When one body is just on the point of sliding over the other body, the maximum force of friction is being exerted, This is called the limiting friction
  • The force of friction is dependent upon the type of materials of the two bodies in contact
  • The limiting frictional force is proportional to the normal force that acts between the bodies in contact
  • The ratio of frictional force to the normal reaction is constant and is known as the coefficient of friction i.e. μ = F/N
  • Limiting static friction is somewhat greater than the kinetic friction
  • The kinetic friction is independent of the relative velocity of the bodies in contact

Related Questions

Which of the following is NOT true about Frictional force? A. Friction is the force which opposes the relative motion of two surfaces in contact. B. The force of friction that acts when a body is moving (sliding) on a surface is called sliding friction. C. Friction in machines wastes energy and also causes wear and tear. D. Rolling friction is much more than sliding friction, the use of ball bearings in a machine considerably reduces friction.
Which of the following statements regarding laws governing the friction between dry surfaces are correct? 1. The friction force is dependent on the velocity of sliding.  2. The friction force is directly proportional to the normal force. 3. The friction force is dependent on the materials of the contact surfaces. 4. The Friction force is independent of the area of contact surfaces.
Consider the following statements: 1. The kinetic friction is always less than the rolling friction. 2. The kinetic friction is always equal to the rolling friction. 3. The kinetic friction is always greater than the rolling friction. Which of the following statement is correct?
While discussing about friction, a teacher gave a number of examples to explain the concept. Some of the examples where friction is useful in our day-to-day life as quoted by the teacher are given below : A. We are able to write because of friction between the tip of the pen and the paper. B. We are able to walk because of friction between our feet and the ground. C. A ball thrown vertically upwards comes back to us due to friction. D. We are able to stop a moving vehicle by applying brakes because of friction. The correct examples were
In the case of the design of friction clutches, the uniform rate of wear theory is used over uniform pressure. The reasons may be the following: 1. It gives lower frictional torque. 2. It gives higher frictional torque. 3. The intensity of pressure is maximum at the inner radius and minimum at the outer radius of the friction or contact surfaces. 4. This concept is prevalent for running and old clutches. Which of the above reasons is correct?
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.
Which of the following is correct about friction? I. Rolling friction is smaller than the sliding friction II. Sliding friction is smaller than static friction 
If, f: A → B and g: B → C. Then which of the following statements are true: 1. f o g exists and it is a function on B. 2. g o f exists and it is function from A to C. 3. f o g does not exists. 4. g o f does not exists.
A body of mass 1 kg is kept on a rough surface having coefficient of friction = 0.25 being pulled by a force of 2N, which frictional force will be acting on the body?
A body of mass 10 kg is resting on a rough horizontal surface of coefficient of friction 0.3. When 15 N force is applied horizontally on the body, then the friction force developed between the surface and the body will be: (Take g = 9.8 m/s2)