Question

a force acts for 10s on a stationary body of mass 100kg after which the force ceases to act.The body moves through a distance of 100m in next 5seconds.calculate the velocity acquired by the body and the acceleration produced by the force.Also find the magnitude of the force.

Answer 1

Dear student,

Given, m = 100 kg
Let F be the force that acts for t = 10 s

we have F=ma ..............(1)

Using Ist eq. of motion :
ie,

v = u + at
since t=10s

v = 10 a ............(2) [ considering the body starts from rest u=0]

After 10s, the force ceases and the body moves with velocity v. In 5 sec, it covers a distance of 100 m.

As, Distance = Speed X time

so, 100 = (10 a) * 5

=>50a=100

=> a=100/50

or acceleration a = 2 m/s^2 ........(3)

Putting this value of 'a' from eq. 3 into eq. 1, we get :

Magnitude of force

F = m a = 100 kg * 2 m/s2 = 200 N

Putting value of 'a' from eq. 3 into eq. 2, we get :

velocity

v = 10 a = 10 s * 2 m/s^2 = 20 m/s

Regards