Block, Ramp, Friction, and Spring

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A block of mass 20 kg is pulled up a 29° incline at a constant velocity, with the work done by the man calculated as 513.1 J. After the string breaks, the block slides down 3.5 m to a frictionless surface, where it hits a spring, compressing it 0.6 m, with its speed upon reaching the surface determined to be 3.91 m/s. The spring constant is calculated to be 849.3 N/m. The discussion reveals confusion regarding the calculation for how far the block rebounds up the incline after being released from the spring. The incline's angle and the displacement along the incline are confirmed as critical factors in the calculations.
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A man pulls a block of mass m = 20 kg up an incline at a slow constant velocity for a distance of d = 3.5 m. The incline makes an angle q = 29° with the horizontal. The coefficient of kinetic friction between the block and the inclined plane is µk = 0.3.

a) What is the work Wm done by the man? Wm = 513.1

At the top of the incline, the string breaks and the block, assumed to be at rest when the string breaks, slides down a distance d = 3.5 m before it reaches a frictionless horizontal surface. A spring is mounted horizontally on the frictionless surface with one end attached to a wall. The block hits the spring, compresses it a distance L = 0.6 m, then rebounds back from the spring, retraces its path along the horizontal surface, and climbs up the incline.

b) What is the speed v of the block when it first reaches the horizontal surface? v = 3.91
c) What is the spring constant k of the spring? k = 849.3
d) How far up the incline d1 does the block rebound? d1 = ?

For picture: https://wug-s.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?cc/DuPage/phys2111/fall/homework/Ch-08-GPE-ME/block_ramp_friction_spring/9.gif
W = ΔKE, W = F*d, U = m*g*h

So I'm stuck on part d.). I thought I could do U = KE - W(friction) = (((1/2)m*v^2) - μmgh*cos(29)) / mg = 0.517 but that didn't work. Any help please?
 
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There is no mention of spring in the problem. How is that?
 
rl.bhat said:
There is no mention of spring in the problem. How is that?

Sorry my bad, I've added the rest of the info after part a.), I've also added a link to the picture included.
 
Angle of the inclined plane is not given. Whether d is the displacement along the inclined plane?
 
rl.bhat said:
Angle of the inclined plane is not given. Whether d is the displacement along the inclined plane?

Yes it is.

The incline makes an angle q = 29° with the horizontal.
 
While going up the kinetic energy of the block = work done against (frictional force + component of weight in the downward direction) + PE.
 
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