Internal explosion, kinetic energy prob

[pb23me]

Homework Statement

an internal explosion breaks an object, initially at rest, into two pieces, one of which has 1.5 times the mass of the other. If 7500 J were released in the explosion, how much kinetic energy did each piece acquire.

Homework Equations

mgy_i+1/2mv_i²=mgy_f+1/2mv_f²

The Attempt at a Solution

not to sure how to go about solving this one..

 

[housemartin]

You don't need that (mgy). Energy released in the explosion will go into kinetic energy of two pieces. And will linear momentum be conserved in this case? if so, use this fact.

 

[pb23me]

ok well understand that m₁v+m₂v=m₁v_f+m₂
and KE=p²/2m ... but i just can't figure out how to put this together with the information that I am given.