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The question:
A block has a mass of 50 g and h is 20 cm. The block has an initial velocity of 2 m/s, and slides down a curve. If the coefficient of kinetic friction between the block and the flat portion of the ramp is 0.2, how far does the block travel along the flat portion of the ramp?
My set up of the problem:
W = 1/2mv^2 + mgh
W = F * D, F = f for friction; f = uK*mg
---> uK * mg* D = 1/2mv^2 + mgh
----> (0.2) (50 g) (10 m/s^2) D = 1/2 (50g) (2 m/s)^2 + (50 g) (10 m/s^2) (.02 m)
I keep getting an answer of 3/5 m (or 0.6 m) for D, the distance that the block travels.
My book says that the answer should be 2 m but I've done it three times now and continue to get the same answer. Any input on this would be appreciated.
A block has a mass of 50 g and h is 20 cm. The block has an initial velocity of 2 m/s, and slides down a curve. If the coefficient of kinetic friction between the block and the flat portion of the ramp is 0.2, how far does the block travel along the flat portion of the ramp?
My set up of the problem:
W = 1/2mv^2 + mgh
W = F * D, F = f for friction; f = uK*mg
---> uK * mg* D = 1/2mv^2 + mgh
----> (0.2) (50 g) (10 m/s^2) D = 1/2 (50g) (2 m/s)^2 + (50 g) (10 m/s^2) (.02 m)
I keep getting an answer of 3/5 m (or 0.6 m) for D, the distance that the block travels.
My book says that the answer should be 2 m but I've done it three times now and continue to get the same answer. Any input on this would be appreciated.
