# Collisions in 2 diemensions

1. Dec 16, 2007

### VanKwisH

1. The problem statement, all variables and given/known data
An object explodes into 3 equal masses. One mass moves east at a velocity of
15.0 m/s . If a second mass moves at a velocity of 10.0 m/s 45degrees south of east.
What is the velocity of the 3rd object

2. Relevant equations
I know m1 = m2 = m3 therefore we have just M

3. The attempt at a solution

I have no idea where to start ..... can anyone help me get started at least??

2. Dec 16, 2007

### Feldoh

Momentum has to be conserved from the Center of mass but you were never given an initial velocity I don't think you can solve it?

EDIT: Did the object explode form rest?

3. Dec 16, 2007

### VanKwisH

yes it exploded from rest, and my teacher said in this case there is no friction .........

4. Dec 16, 2007

### Feldoh

Momentum has to be conserved for the center of mass of the individual particles, which equaled 0 before the explosion, can you see where to go form here?