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

• and the cloth both acquire positive charge.

• becomes positively charged while the cloth has a negative charge.

• and the cloth both acquire negative charge.

• becomes negatively charged while the cloth has a positive charge.

Lightning conductor cannot protect a building from lightning.

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

Earthquakes can be predicted in advance.

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

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

Name the scale on which the destructive energy of an earthquake is measured. An earthquake measures 3 on this scale. Would it be recorded by a seismograph? Is it likely to cause much damage?

Suggest three measures to protect ourselves from lightning.

Explain why a charged balloon is repelled by another charged balloon whereas an uncharged balloon is attracted by another charged balloon?

Describe with the help of a diagram an instrument which can be used to detect a charged body.

If two pens made of the same material are rubbed against dry hair and brought closer to each other, will they attract or repel each other?

What kind of electric charge gets developed on the glass rod, when it is rubbed with a piece of silk cloth?