Question

A force acts for 0.2 sec on an object having mass 1.4 kg initially at rest. The force stops to act but the object moves through 4m in the next 2 sec. Find the magnitude of the force? (Ans: 14 N )

Answer 1

Answer ⇒ 14 N.

Solution ⇒

As per as the question, the force has stopped acting, thus, the object will move with constant velocity.

Given, Distance covered = 4 m.

Time taken = 2 seconds.

∵ Velocity = Distance/Time

∴ v = 4/2

= 2m/s

Now, Time = 0.2 seconds.

Using the First equation of motion,

a = (v-u)/t

A = (2 - 0)/0.2

A = 10 ms⁻²

Now, Using the Newton's second law,

Force = mass × acceleration.

∴ Force = 1.4 × 10

⇒ Force = 14 N

Hence the magnitude of the force is 14 N.

Hope it helps.