How can I solve for the velocities of two balls after an off-center collision?

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An off-center elastic collision occurs between a moving ball at 11 m/s and a stationary ball of equal mass, resulting in the moving ball being deflected at a 30° angle. To solve for the velocities after the collision, conservation of kinetic energy and conservation of momentum equations are necessary. The initial kinetic energy is known, but the final kinetic energies of both balls need to be determined. The conservation of momentum must be applied separately in the x and y directions using the components of the velocities. Understanding these principles is crucial for preparing for an upcoming exam on this topic.
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A ball moving at 11 m/s makes an off-center elastic collision with another ball of equal mass that is initially at rest. The incoming ball is deflected at an angle of 30° from its original direction of motion. Find the velocity of each ball after the collision.

Ball moving initally at 11 m/s
(a) magnitude m/s (moving ball)?
(b) direction ° (from the original direction of motion)?

Ball initally at rest
(c) magnitude m/s?
(d) direction ° (from the original direction of motion)?

How do I start this problem? Someone in my recitation had a problem similar to this and used three equations with three unknowns. I think it was conservation of KE, conservation of momentum, and something else but i don't remember.

My book briefly talks about this, but there are no sample problems to work with.
Thanks
 
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You have three equations: One conservation of energy and two for conservation of momentum (1 for the x direction and 1 for the y direction). Use the components of the velocity in the x and y directions for the conservation of momentum in the x and y direction, respectively. For the conservation of energy you just use the magnitude of the velocities.
 
I'm having trouble setting up these equations. For conservation of energy, I have the initial KE, but final KE I don't know what the final kinetic energies of each ball is. I think the incoming ball is (1/2)m(11 m/s)^2*sin (30) but the final kinetic energy of the ball initially at rest I don't know what that is.
For the conservation of momentum, the initial momentum's are easy to calculate, but the final momentums are what I don't know (in both the x and y components) I have a feeling these type of questions will be on the exam coming up on Thurs. so I want to be able to understand how to do them.
Thanks
 
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