Which of the following cannot be charged easily by friction?

(a) A plastic scale

(b) A copper rod

(c) An inflated balloon

(d) A woollen cloth

When a glass rod is rubbed with a piece of silk cloth the rod

(a) and the cloth both acquire positive charge.

(b) becomes positively charged while the cloth has a negative charge.

(c) and the cloth both acquire negative charge.

(d) becomes negatively charged while the cloth has a positive charge.

Write T against true and F against false in the following statements.

(a) Like charges attract each other. (T / F)

(b) A charged glass rod attracts a charged plastic straw. (T / F)

(c) Lightning conductor cannot protect a building from lightning. (T/F)

(d) Earthquakes can be predicted in advance. (T / F)

Sometimes, a crackling sound is heard while taking off a sweater during winters. Explain.

Explain why a charged body loses its charge if we touch it with our hand.