Q19 of 42 Page 33

A person driving a car suddenly applies the brakes on seeing a child on the road ahead. If he is not wearing seat belt, he falls forward and hits his head against the steering wheel. Why?

On seeing a child on the road when a person applies breaks suddenly, the lower part of person slows rapidly with the car, but the upper part of driver continues to move with same speed in the same direction due to the inertia of motion his head car hit with steering.


More from this chapter

All 42 →
17

A person of mass 50 kg stands on a weighing scale on a lift. If the lift is descending with a downward acceleration of 9 m s-2, what would be the reading of the weighing scale? (g = 10 m s-2)

 18

The position time graph of a body of mass 2 kg is as given in Fig. 5.4. What is the impulse on the body at t = 0 s and t = 4 s.

 20

The velocity of a body of mass 2 kg as a function of t is given by v(t) = 2t î + t2 j. Find the momentum and the force acting on it, at time t= 2s.

 21

A block placed on a rough horizontal surface is pulled by a horizontal force F. Let f be the force applied by the rough surface on the block. Plot a graph of f versus F.