Work By Gravity & Inclined Planes Video Lessons

Concept

# Problem: a) A person is riding on a Ferris wheel of radius r. He starts at the lowest point of the wheel. When the wheel makes on complete revolution, is the net work done by the gravitational force positive, zero, or negative? Do you need to know how the speed of the person changed before you can answer the question?b) Suppose the person started at the highest point of the wheel. What is the net work done by the gravitational force when he reaches the lowest point?

###### FREE Expert Solution

a)

We know that the gravitational force is conservative.

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###### Problem Details

a) A person is riding on a Ferris wheel of radius r. He starts at the lowest point of the wheel. When the wheel makes on complete revolution, is the net work done by the gravitational force positive, zero, or negative? Do you need to know how the speed of the person changed before you can answer the question?

b) Suppose the person started at the highest point of the wheel. What is the net work done by the gravitational force when he reaches the lowest point?