A stationary object of mass 4kg is set in motion by a net force of 50N. If the object attains is speed of 5ms−¹ in time. Calculate the value of t.

A. 0.20s
B. 0.40s
C. 0.63s
D. 0.80s
E. 1.30s

Correct Answer:

Option B – 0.40s

Explanation

F = ma = MV/t ∴ t = MV/F = 20/50 = 0.40s