Question

11. A body of mass 1 kg is kept at rest. A constant force of 6.0 N starts acting on it. Find the time taken by the body
to move through a distance of 12 m.
[Ans. 2 s]
12. A force of 4 N acts on a body of mass 2 kg for 4 s. Assuming the body to be initially at rest find a. its velocity
when the force stops acting b. the distance covered in 10 s after the force starts acting. [Ans. a. 8 m s1 b. 100 m]​

Answer 1

Explanation:

Mass of body =1kg

Force acting on body = 6N

According to Newton 2nd law of motion

F=ma

6 =1a

a = 6 m/s^2

Distance to be travelled = 12 m

Initial velocity(u) of body =0m/s (because it is at rest)

Using 2nd kinematic equation

x = ut + 1/2at^2

12 = 0+ 1/2 at^2

12*2 = 6t^2

24/6 = t^2

4 =t^2

Square root

t=2sec