Question

A crate rests on a frictionless incline, and is attached to a bucket of nails through a frictionless and weightless pulley as is shown.
Crate = 12.0 Kg Bucket = 25.0 Kg Angle = 20 degrees





a) You may assume that the crate accelerates up the incline. Calculate the magnitude of the acceleration of the crate. (8 points)










a = ________

b) If the acceleration of the crate was calculated to be a negative value, what could be said about the assumption in part a) that the crate moved up the incline? (2 points)






c) What is the magnitude of the Normal force of the incline pushing up on the crate (find N the Normal Force) ? (6 points)







N = _________

d) It turns out that there really is friction between the crate and the incline. The value of the friction coefficients is Us = 0.25, and Uk = 0.15. What will the acceleration be of the crate up the incline if you take in account friction? (8 points)











a = _________

e) A workman who was watching the crate accelerate up the incline decides he wants to adjust the system so that the crate maintains a steady speed while traveling up the incline. He removes nails from the bucket to achieve this goal. Taking into account the friction from part d), what should the new mass of the bucket of nails be to make this happen? (8 points)






m = ___________

Answer 1