91Ó°ÊÓ

Calculate How much work is required for a 73-kg runner to accelerate from rest to a speed of \(7.5 \mathrm{~m} / \mathrm{s}\) ?

A \(0.14-\mathrm{kg}\) pinecone is \(16 \mathrm{~m}\) above the ground. What is its gravitational potential energy?

Calculate A \(0.14-\mathrm{kg}\) pinecone is \(16 \mathrm{~m}\) above the ground. What is its gravitational potential energy?

It takes \(13 \mathrm{~N}\) to stretch a certain spring \(9.5 \mathrm{~cm}\). How much potential energy is stored in this spring? (Hint: Calculate the spring constant first, then the potential energy.)

Calculate It takes \(13 \mathrm{~N}\) to stretch a certain spring \(9.5 \mathrm{~cm}\). How much potential energy is stored in this spring? (Hint: Calculate the spring constant first, then the potential energy.)

In a tennis match a player wins a point by hitting the \(0.059-\mathrm{kg}\) ball sharply to the ground on the opponent's side of the net. If the ball bounces upward from the ground with a speed of \(16 \mathrm{~m} / \mathrm{s}\) and is caught by a fan in the stands when it has a speed of \(12 \mathrm{~m} / \mathrm{s}\), how high above the court is the fan? Ignore air resistance.

A crow drops a \(0.11-\mathrm{kg}\) clam onto a rocky beach from a height of \(9.8 \mathrm{~m}\). What is the kinetic energy of the clam when it is \(5.0 \mathrm{~m}\) above the ground? What is its speed at that point?

A crow drops a 0.11-kg clam onto a rocky beach from a height of \(9.8 \mathrm{~m}\). What is the kinetic energy of the clam when it is \(5.0 \mathrm{~m}\) above the ground? What is its speed at that point?

Apply The potential energy of an object decreases by \(10 \mathrm{~J}\). What is the change in the object's kinetic energy, assuming there is no friction in the system?

The potential energy of an object decreases by \(10 \mathrm{~J}\). What is the change in the object's kinetic energy, assuming there is no friction in the system?