Question

In 10 seconds a body of mass 6kg is dragged to 8m with a steady force of 20N. The KE of the body is?

Answer 1

Answer:

160 Joules.

Explanation:

I think the body is dragged through 8m starting from rest.

We need to find the acceleration of the body.

Since F=ma,

a = F/m = 20/6 = 10/3 m/s²

We need to find the velocity of the body after travelling 8m.

Therefore by using equation of motion,

v² - u² = 2×a×S

since u=0

v² = 2×a×s

v²= 2 × 10/3 × 8 = 160/3

We know, Kinetic Energy= 1/2 × m × v²

= 1/2 × 6 × 160/3 = 160 Joules.

Hence your answer is 160 Joules.