Max Height of m1 After Elastic Collision on Frictionless Track

[chevyboy86]

Two blocks are free to slide along a frictionless wooden track. A block of mass m1=5 kg is released from point A. Protruding from its front end is the north pole of a strong magnet, repelling the north pole of an identical magnet embedded in the back end of the block of mass m2=10 kg, initially at rest. The two blocks never touch. Calculate the maximum height to which m1 rises after the elastic collsion.

m1 is initially at a height of 5 meters. I don't know what equation to use for this problem.

 

[Fermat]

Assume convservation of energy.

Balance momentum before and after impact.
Balance kinetic energy before and after impact.

 

[Locrian]

There must be some sort of diagram that goes with this? I believe there is information missing here.

Edit: Though I guess if you work to make the problem meaningful, conservation of energy will make most other information unnecessary.

 

[Fermat]

Yeh, I would figure that it is a (vertically) circular track, since m1 has a height and the question asks for a final height.