Question

A box falls to the ground from a delivery truck traveling at 30 m/s. After hitting the road, it slides 45 meters to rest. How long does it take the box to come to rest? 

(A) 0.67 s 

(B) 1.5 s 

(C) 2.0 s 

(D) 3.0 s 

(E) 6.0 s

Answer 1

Correct option (D) 3.0s

v_i = 30m, v_f = 0, d = 45m, bar v = (v_i + v_f)/2 = d/t