Question

(i) Give reasons for the following:
a. A wide steel belt (caterpillar tracks) is provided over the wheels of an army tank.
b. A plastic comb rubbed over dry hair can pick up tiny pieces of paper.
c. Astronauts wear special pressurised suits.

Answer 1

Answer:

A-1

A wide steel belt is provided over the wheels of an army tank to increase the area of contact and so the pressure on the belt of the heavy weight of the tank gets reduced. This prevents the tank from sinking into the ground.

A-2

A plastic comb when rubbed with hair gets electrically charged and can attract small pieces of paper. This is due to the presence of electrostatic forces. ... This happens because by rubbing charge get formed on the comb. As the nature it will attract any opposite charged particles, hence, it will attract the paper

A-3

Spacesuits are specially designed to protect astronauts from the cold, radiation and low pressure in space. They also provide air to breathe.

Answer 2

Answer:

A wide steel belt is provided over the wheels of an army tank so that they exert less pressure on the ground and do not sink into it.