2D collision between 3.0kg and 4.0kg masses with given velocities

[tha-wanderer]

hey, just need help on this question. i know the answer but i need all the working out as i have a test tomorrow and don't understand how and when to use the equations of motion and change in momentum etc.

A 3.0kg mass moving at 4.0ms at 135degress collides with a 4.0kg mass moving at 2.0ms at 315 degrees. The collision occurs over 0.20s and the 3.0kg mass is measured to be moving off at 1.0ms at 135 degrees. Find:

a) the final velocity of the 4.0kg mass
b) the acceleration of the 3.0kg mass
c) The force acting on each mass.

Thanks a lot people!

 

[Hootenanny]

According to the rules of our forum, one is required to show one's own efforts before requesting assistance.

 

[HallsofIvy]

In other words, what do you know and what help do you need?