A person is riding on a Ferris wheel. When the wheel makes one complete turn, is the net work done by the gravitational force positive, negative, or zero?
Justify your answer.
What to you think? After one complete turn the elevation remains unchanged.
Elevation determines gravitational potential energy
inetial veiocity is zero
To determine the net work done by the gravitational force on a person riding a Ferris wheel, we need to understand the relationship between gravitational potential energy and elevation.
Gravitational potential energy is the energy associated with an object's position in a gravitational field. It depends on the height or elevation of the object above a reference point. In the case of a Ferris wheel, as the person completes one full turn, their elevation remains unchanged. This means that the starting and ending elevation is the same.
Now, to answer the question, we need to consider the work-energy theorem. According to the work-energy theorem, the net work done on an object is equal to the change in its kinetic energy. In this case, since the net work is done by the gravitational force, it is equal to the change in gravitational potential energy.
Since the elevation remains unchanged after one complete turn, the change in gravitational potential energy is zero. This implies that the net work done by the gravitational force on the person is also zero. Therefore, the answer is that the net work done by the gravitational force is zero.
To summarize:
Net work done = Change in gravitational potential energy
Since the elevation remains the same after one complete turn, there is no change in gravitational potential energy.
Hence, the net work done by the gravitational force is zero.