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Ram is asked to observe the athlete running in a circular track with constant speed find work done by centripetal force

Ram is asked to observe the athlete running in a circular track with constant speed find work done by centripetal force Correct Answer work done will be zero

CONCEPT:

  • Uniform circular motion: The movement of a body following a circular path is called a circular motion.
    • The motion of a body moving with constant speed along a circular path is called Uniform Circular Motion.
    • Here, the speed is constant but the velocity changes.
    • For a particle to move along the circular path it should have acceleration acting towards the center, which makes it move in a circular path.
    • As acceleration is perpendicular to the velocity of a particle at every instant, it is only changing the direction of velocity and not magnitude and that’s why the motion is uniform circular motion.
    • The angle between the velocity and acceleration is always 90° so work is done will be zero.

 

​Figure:

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FORMULA:

Work done = F.dscosθ

where, F = force in newton, ds = displacement, θ = angle between velocity and acceleration

EXPLANATION: 

  • As per the above discussion as speed is constant so motion is uniform motion and the object is always accelerated.
  • In a circular motion, force is always acting towards the centre, and displacement is along the circumference, and the angle is always 90°. 

 

Work done  = F.ds cos θ

W.D = F.ds cos 90° = 0

The correct option is 0.

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