A ball is spun in a circle with constant speed, parallel to the ground. Ifthe center of the circle is kept at the same height but the circle of motionchanged to be perpendicular to the ground and keeping the same speed, waswork done on the ball?

2 answers

If it kept the same speed, then work = m g *diameter had to be done to reach the top from the bottom of the circle.
By the way in real life the thing would slow down a little on the way up.