Consider a uniform circular motion of an object of mass m with a constant speed v along a circular path of radius r. What is the work done by the centripetal force on the object over a quarter of the circular path?

💡 Solution & Explanation

In uniform circular motion, the centripetal force acting on the object is always directed towards the center of the circular path, while the instantaneous displacement vector of the object is tangential to the path at any given point. The angle between the centripetal force and the displacement vector is always ninety degrees, meaning the scalar dot product representing work done is zero. Incorrect choices confuse force magnitude or momentum with mechanical work. The work-energy theorem states that net work done on an object equals its change in kinetic energy.