Physics
posted by Physics .
A 0.409 kg block is attached to a horizontal spring that is at its equilibrium length, and whose force constant is 19.5 N/m. The block rests on a frictionless surface. A 0.0500 kg wad of putty is thrown horizontally at the block, hitting it with an initial speed of 2.32 m/s and sticking. How far does the puttyblock system compress the spring?

From conservation of momentum, find the intial velocity of the block/putty mass.
Then, KE= 1/2 k x^2 solve for x. 
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