Pendulums colliding - collision

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In the figure View Figure the upper ball is released from rest, collides with and the stationary lower ball, and sticks to it. The strings are both 50.0 cm long. The upper ball has mass is 2.00 kg and it is initially 10.0 cm higher than the lower ball, which has mass 3.00 kg.

Diagram of two pendulums hanging from a common pivot: a ball on a 50.0 cm string at the bottom, and a ball released from a higher position on a diagonal string, with a dashed vertical arrow labeled 10.0 cm marking the height difference between them.


Find the maximum angular displacement of the motion after the collision.

I've found omega, if that helps.
 
since we don't know what omega is, it doesn't.

Convert the potential energy the ball being held up starts with into the kinetic energy it will have when it strikes the bottom ball. Then use conservation of momentum for an inelastic collision, and convert the new kinetic energy to the maximum potential energy the system can achieve. From there, use trig
 
superdave said:
In the figure View Figure the upper ball is released from rest, collides with and the stationary lower ball, and sticks to it. The strings are both 50.0 cm long. The upper ball has mass is 2.00 kg and it is initially 10.0 cm higher than the lower ball, which has mass 3.00 kg.

Diagram of two pendulums: a ball hanging vertically from a pivot at top left, and a second ball on a string displaced to the right, with its center 10.0 cm above the lower ball's level, shown by dashed horizontal lines and a vertical arrow.


Find the maximum angular displacement of the motion after the collision.

I've found omega, if that helps.

Use conservation of energy to find the speed of the first mass just before it hits the second one. Then use momentum conservation to find the speed of the two masses combined just after the collision (when they are still at the lowest point). Finally, use conservation of energy again to find how high they will swing up. Once you have that, simple geometry will give you the angle they reach.
 
can you give me a hint with the trig? Because I can only find one side, and the right angle. I need at least one more angle or side.