Awooden block of mass m = 9 kg starts from rest on an inclined plane sloped at an angle θ from the horizontal. the block is originally located 5m from the bottom of the plane. if the block, undergoing constant acceleration down the ramp, slides to the bottom in t = 2 s, and θ = 30º, what is the magnitude of the kinetic frictional force on the block? ƒk =

f = 0.283

Explanation:

With the given values x=5m and t=2s, the acceleration a of the block must be:

(1)

The sum of all forces in the inclined plane must be:

(2)

Solving equation2 for the acceleration a:

(3)

Using equations 1 and 3 to solve for f:

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