Answer to Question #179352 in Physics for wantutri apple

Question

A box of mass 10 kg is moving with a constant velocity of 5m/s on a horizontal surface. The coefficient of sliding friction between box and the surface is 0.20. Find a. What horizontal force is needed to maintain the motion. b. If force is remove, time the object stops.

Answer 1

(a)

$F=ma\to F-F_f=0\to F=F_f=\mu mg=0.2\cdot10\cdot9.81=19.62\ (N)$ . Answer

(b)

$v=v_0-at$

$F_f=ma\to a=F_f/m=19.62/10=1.962\ (m/s^2)$

$0=v_0-at\to t=v_0/a=5/1.962=2.55\ (s)$ . Answer