A force acts for 0.1 s on a body of mass 2.0 Kg initially at rest. The force is then withdrawn and the body moves with a velocity of 2 m s-1. Find the magnitude of force.

Time (t) = 0.1 s

Mass (m) = 2.0 Kg

Initial velocity (u) = 0

Final Velocity (v) = 2 m s^-1

The 1^st equation of motion states that;

v = u + at

⇒ 2 = 0 + a × 0.1

⇒ a × 0.1 = 2

⇒ a = 2/0.1 = 20 m s^-2

Hence, acceleration of the body = 20 m s^-2

Now,

Force (f) = mass (m) × acceleration (a)

= 2 × 20 = 40 N

Hence, Magnitude of force = 40 N