How Do Speed and Direction Change for Two Colliding Pool Balls?

[kapil1089thek]

I have two balls with d1 and d2 as their direction, and I have the speed s1 and s2, d1 and d2 are in radians showing the angle made with positive direction of x-axis and in anticlockwise direction i.e 0<=d1 and d2<2*pi
their positions are (x1,y1) and (x2,y2) when they collided

after collosion
what would be their speed, and direction?

 

[diazona]

What have you tried?

There are some formulas listed on the Wikipedia page
http://en.wikipedia.org/wiki/Elastic_collision#Two-_and_three-dimensional
that could be adapted to your situation.

 

[frustr8photon]

shouldn't their positions be the same when they collide?

basically you want to split the problem up into two problems: momentum is conserved in both the x and y directions, independently. also it looks like you're assuming completely elastic collisions.

 

[frustr8photon]

Sorry--you will need to use conservation of energy, too.
this plus both equations for conservations of momentum should be enough to solve the problem.