Q12 of 35 Page 143

When a horizontal force P acts on a cart of mass 20 kg it moves with a uniform velocity on a horizontal floor. When a force of 1.2P acts on the cart it moves with an acceleration of 0.05 metre per second square. Find the value of P.

Friction inhibits the movement of the cart.

Let friction be F and force is P.


As the velocity is zero.


F – P = 0


F = P


Force acting is 1.2 P on cart,


For Acceleration, a: 1.2P – F = ma


1.2P – P = 20kg ×0.05m/s2


0.2P = 20kg × 0.05m/s2


P = 5N


More from this chapter

All 35 →
10

A gun of mass 3 kg fires a bullet of mass 30 g. The bullet takes 0.003 seconds to move through the barrel of the gun and acquires a velocity of 100 m/s.

Calculate a) the velocity at which the gun recoils


b) the force exerted on the gunman due to the recoil of the gun.

 11

N balls each of mass m impinge elastically in each second on a surface with velocity u. The average force experienced by the surface will be?

 13

More the mass the more difficult it is to move the body from rest'. Explain this statement by giving an example.

 14

What are different types of inertia? Give examples.