Question

44. A body of mass 4 kg initially at rest is subjected to a force 16 N, K.E acquired by the body at the end of 10 s is [ ]
a) 1600 J b) 6400 J c) 16 J d) 3200 J

Answer 1

Answer:

K.E = 3200J

Explanation:

Given, m = 4 kg

F = 16 N

t = 10s

Force applied on the body causes acceleration. This acceleration increases the velocity of the body. W.K.T,

F = ma

a = F/m

a = 16/4

a = 4 m/s²

From equations of motion for uniform accelerated body,

v = u + at

v = 0 + 4(10)

v = 40 m/s²

K.E = mv²/2

K.E = 4(40)²/2

K.E = 3200 J

Thank you.