Give reasons for the following:
(a) Your hair stands on its ends while removing a sweater or when you pull off your hat.
(b) You see a streak of lightning before you hear the thunder associated with it.
(c) A rice grain tied to a thread is attracted to a plastic comb that was just used to comb hair.
(d) Anand found that balloons rubbed with his sweater did not stick to the walls of his bathroom where he had just taken a bath with hot water.

Open in App

Solution

(a) Our hair stands on end while we remove a sweater or our hat because it acquires static electricity owing to friction.

(b) We see lightning before we hear thunder because light travels much faster than sound.

(c) On combing hair, a plastic comb acquires static electricity, so when it is brought near a rice grain, the grain gets attracted towards it.

(d) A wet wall acts like a conductor, and when a charged balloon is brought near it, the charges move from the balloon to the wall, and the balloon gets discharged.

Suggest Corrections

Similar questions

What will you observe when the metal top of an electroscope is touched with a plastic comb rubbed in dry hair ? Give reason for your answer.

When a plastic comb is rubbed with dry hair, it acquires some charges due to which it attracts tiny pieces of paper. But when a plastic comb is rubbed with wet or oiled hair the same does not happen. Why?

Q. On a cold, dry day, a child takes two balloons and rubs them against his sweater.
(a) When taken near each other, the balloons repel each other.
(b) When one is taken near the wall, it sticks to it.
Give reasons for the above observations.

If you rub a metal comb in your hair it does not get charged why

Q. When a plastic comb is rubbed with hair, it acquires some charges due to which it attracts tiny pieces of paper. The type of charge, which the comb acquires from the hair is ___.

Join BYJU'S Learning Program