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Why is the work done on an object moving with uniform circular motion zero?

In uniform circular motion work done on an object is zero, because force acting on the object is always perpendicular to its velocity and displacement.

In uniform circular motion,

i. The speed of the object is same throughout but the velocity is changing because the direction of motion of object is continuously changing.

ii. The object is accelerating, and acceleration is towards the center of circular path in which object is moving do force is also acting towards the center of the circular path i.e. perpendicular to the direction of motion.

The Path of circular motion of the object, direction of its velocity, displacement, acceleration and Force at any instant has been shown in the figure :

As we can see direction of Velocity and displacement at any instant is along the tangent of circle and is perpendicular to direction of acceleration and force i.e. angle between force and displacement at any instant is 90⁰.

Now we know work done on an object due to a force is given by relation:

W = F× s × cos