The Student Room Group
A particle P of mass 0.2kg is at rest 3m from the edge of a horizontal bench. P receives an impulse of magnitude 4 NN s.

The bench is rough and the coefficient of friction between P and the bench is 2/5.

(c) the speed of P when P reaches the edge of the bench.
Reply 2
Basically:

Wd by friction = Gain in PE + Gain in KE

-2.352 = 0 + (1/2 x 0.2 x v^2) - (1/2 x 0.2 x 20^2)

-2.352 = 0.1v^2 - 40

37.648 = 0.1v^2

376.48 = v^2

So v=19.4 m/s to 1d.p. hope that helps!

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