Question

Explain the construction and working of the gold leaf electroscope.

Answer 1

1. A gold-leaf electroscope is an instrument used to check if a body is electrically charged or not and the nature of the charge on the body.
2. Construction: It consists of a brass strip, brass cap, shellac seal, brass rod, glass bell jar, gold leaf, tin foils, and wooden base as shown in the figure below.
3. 
4. A glass bell jar is placed on an insulator i.e., a wooden base. The mouth of the jar is closed with a cork and sealed with a shellac seal which serves as an insulator and supports a brass rod passing through it.
5. A brass cap is provided at the upper end of the brass rod. Inside the jar, the brass rod is fitted with a brass strip, and a small gold leaf is also loosely held to the strip. At the bottom of the jar, tin foils are earthed which are fixed and help the charge on gold foil to remain for a long time.