Question

define gold leaf electroscope in short

Answer 1

When a charge is put on the disc at the top it spreads down to the plate and leaf. This means that both the leaf and plate will have the same charge. Similar charges repel each other and so the leaf rises away from the plate - the bigger the charge the more the leaf rises.

The leaf can be made to fall again by touching the disc - you have earthed the electroscope. An earth terminal prevents the case from becoming live. The electroscope can be charged in two ways:

(a) by contact - a charged rod is touched on the surface of the disc and some of the charge is transferred to the electroscope. This is not a very effective method of charging the electroscope.

(b) by induction - a charged rod is brought up to the disc and then the electroscope is earthed, the rod is then removed.

Answer 2

The gold leaf electroscope. This is an instrument for detecting and measuring static electricity or voltage. A metal disc is connected to a narrow metal plate and a thin piece of gold leaf is fixed to the plate