• FIGURE shows the 55 kg crate is at rest and the spring is initially un stretched. Knowing the spring has a stiffness of k = 2 kN/m and the coefficient of kinetic friction between the crate and the plane is μk = 0.35.(i) determine the frictional force acting on the crate, Ff.(ii) calculate the speed of the crate, v, at the instant when the compression of the spring is x = 1.7 m.
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k=2 kN/m- 45 10 m