Question

You are provided with s positively charged gold leaf electroscope. State what happens when:
1) A glass rod rubbed with a silk is brought near the disc of electroscope.
2) A glass rod rubbed with silk is rolled on the disc of electroscope.
3) An uncharged metal rod is brought near the disc of electroscope.

Answer 1

a) A glass rod rubbed with silk will acquire positive charge, so when it is brought near the disc of electroscope then the leaves will attract each other and hence contract. b) A ebonite rod under the above circumstances will get negatively charged and hence as per the above observation the leaves with dilate. c) If the metal rod is electrically neutral then, nothing will happen to the leaves.