Classical Mechanics
# Momentum

A \(69\text{ kg}\) stuntman jumps out of a window and lands on a trampoline \(5\text{ m}\) below. What is the magnitude of his momentum at the point he hits the trampoline?

**Assumptions**

- The air resistance is negligible
- The gravitational acceleration is \(g=10\text{ m/s}^2.\)

An object of mass \(4\text{ kg}\) is thrown straight upward into the air at a velocity of \(15\text{ m/s}\) from the edge of a cliff. Let \(p_1\) be the momentum of the object \(1\) second after the throw, and \(p_{4}\) the momentum of the object \(4\) seconds after the throw. Then what is \(\displaystyle{\frac{p_{4}}{p_1}}?\)

Assume that gravitational acceleration is \(g=10\text{ m/s}^2.\)

A \(1\text{ kg}\) ball is rolling on the floor at \(4\text{ m/s}.\) Find the momentum of the ball.

An object initially at rest falls freely in an atmosphere free of air resistance. After \(t\) seconds, the kinetic energy of the object is \(x\text{ J}\) and the momentum of the object is \(y\text{ kg}\cdot{m/s}.\) If \(x=y,\) what is the value of \(t?\)

Assume that gravitational acceleration is \(g=10\text{ m/s}^2.\)