Physics
posted by Dakota HELP!! Assignment due within 30mts!!! on .
A 10kg block is released from the top of a ramp 45m high. the track is frictionless except for a 6m stretch in the middle. when the block reaches the end, it compresses the k=2250N/m spring a distance of 0.030m. Find the coefficient of friction over the rough patch in the middle.

work this as energy.
Initial PE=Final PE+friction work
Initial PE=mgh
final PE=1/2 k x^2 where k=2250, x.030
frictionwork= mg*cosTheta*mu*6
So, put this into the equation, solve for mu. However, the angle of the ramp needs to be known to solve it, I don't see it given, or data given to calculate it. 
PE = KE + W(fr),
m•g•h = m•v^2/2 + μ•m•g•cosα•s,
KE = PE(spring)
m•v^2/2 = kx^2/2,
Then,
m•g•h = kx^2/2 + μ•m•g•cosα•s,
μ ={ m•g•h  kx^2/2}/ m•g•cosα•s.
It is necessary to know the angle α