Question

What happens when the end of the paper clip of the electroscope is touched by hands ?
A. Electric current is produced
B. Foil strips remain as it is
C. Foil strips collapse
D. None of these

Answer 1

Hint: An electroscope is an early scientifically used instrument which is used to detect the presence of electric charge on a body. The amount of charge on a body is proportional to the voltage .In electrostatics opposite charges attract each other while charges repel each other. Neutral body neither attracts or repels.

Complete step-by-step solution:Working of an electroscope :- An electroscope is a device that detects static electricity by using thin metal of plastic leaves, which gets separated when charged.
 An object with a suspended static electric charge is brought near the metal plate or ball of the electroscope . Electrical charges move to the metal and down to the foil leaves, which then repel each other. Since each leaf has the same charge ( positive or negative ) , they repel each other.
When the end of the paper clip of the electroscope is touched by hands the charge on foil strips gets discharged through the body as we touch the paper clip of the electroscope by hands, hence the foil strips collapse.
Hence option ( C ) is the correct option.

Note:- The electroscope was the first electrical measuring instrument . The pith ball electroscope and the gold-leaf electroscope are two classical types of electroscope that are still used to demonstrate the principle of electrostatics.
In Gold – leaf electroscope , we use leaf of gold because the metal gold is more than any metal. Another reason is that gold is very less reactive , if we put a reactive metal as trey’s substance , then that metal will react with the electrons that pass through it and will leave the observer a hard to have a good view.
Apart from gold , copper can be used as it is malleable and also less reactive.