Hi guys, I am new here and I am having a LOT of trouble with this new momentum stuff, which I failed in(adsbygoogle = window.adsbygoogle || []).push({});

Here's a question:

A billiard ball has mass 210 g. It's hit with spin and bounces off the side of a table. The initial speed of ball is 1.6 ms-1 (at angle of 60 degrees) and its final speed is 0.8ms-1 (at angle of 30 degrees)

1) Find the change in the momentum of ball due to collision

I had trouble even starting the question. I drew the normal between the collision, and did 90-30=60 to find the inside angle and 90-60=30 for the other. Is anyone able to give me a hint on what formula to use? I'm not familiar with this because I usually do the problems with same initial and final speed.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Billiard ball physics problem

**Physics Forums | Science Articles, Homework Help, Discussion**