Question

A 10.0 kg block is resting on a horizontal surface when a force P is applied to it for 7.00 seconds. The variation of P with time is shown in the figure where P is in Newtons and t is in seconds. If the coefficients of static and kinetic friction between the block and the surface are μs = 0.600 and μk = 0.400 respectively, and g = 10.0 m/s2 calculate

a) [2] The time t_1 at which the block begins to move.
b) [4] The maximum velocity reached by the block.
c) [4] The total time (Δt) during which the block is in motion.

10 kg solle P, N P(t)=-6.25t2+50t A 100+ →t, s

Answer 1

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