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Question
Why is the work done on an object moving with uniform circular motion zero?
Solution
Work done on an object is given as `W = F xx S costheta`
In circular motion, the direction of force acting on the object is radially inward and the direction of motion of the object is tangential to the circular path at every instant of time. Thus, the angle `theta` between the force vector and displacement vector is always 90o i.e. `theta = 90^circ`.
Hence, `W = F xx S cos 90 = 0`
Hence, the work done on an object moving in uniform circular motion is zero.
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