Homework Help: Impulse help

1. Mar 7, 2005

Jayhawk1

Impulse help!!

A 0.09 kg tennis ball with a speed of 43.2 m/s strikes the ground at a 45.4 degree angle and rebounds with the same speed and the same angle (see the figure below). What is the magnitude of the impulse given to the ball by the ground?

Does anyone have any clue?? I sure don't.

2. Mar 7, 2005

Erienion

Impulse = change in momentum / time.

Guess you can start by finding dP

3. Mar 7, 2005

cepheid

Staff Emeritus
Jayhawk,

This isn't just some random problem designed to make you do some math. Ask yourself, "what key concept about physics that I am supposed to learn about is being tested here?" Do you know the definition of impulse? (If you don't, then learning it would be a good place to start, considering that's what you're being asked to calculate!) Furthermore, have you heard of the impulse-momentum theorem?

Last edited: Mar 7, 2005
4. Mar 7, 2005

Jayhawk1

I don't know what to do with the angles...

5. Mar 7, 2005

dextercioby

Use the geometry and the property of vectors to be decomposed after orthonormal coordinates.In your case,one component from the initial vector will not transfer momentum at all,while the other will transfer it all.

Daniel.