physics
posted by James .
A spring (k=200N/m) is fixed at the top of a frictionless plane inclined at an angle of 40 degrees. A 1 kg block is projected up the plane from an initial position that is distance d=0.60m from the end of the relaxed spring, with an initial kinetic energy of 16J. A) What is the kinetic energy of the block at the instant it has compressed the spring 0.20m? B) With what kinetic energy must the block be projected up the plane if it is to stop momentarily when it has compressed the spring by 0.40m?

Initial KE+Intial PE=finalKE+finalPE
16J+1/2 k .6^2=finalke+ 1/2k .2^2
solve for finalKE