Question

A glass rod was rubbed with silk. A cloth X (not silk)  was rubbed with another rod Y (not glass). Glass rod attracted rod Y, the electric charge on cloth X  is similar to that off ________
1. Glass rod
2. Silk cloth
3. Y
4. Both  (2) and (3)

Answer 1

Correct Answer - Option 1 : Glass rod

Concept:

• Electric charge: When two objects are rubbed, both acquire charge. 
• Electric charges are of two types, positive and negative.
• When two objects are rubbed, one acquires a positive charge and another acquires a negative charge. 
• Like charges attract and unlike charges repel each other. 
• By convention, when the glass rod is rubbed with the silk, the glass rod acquires a positive charge and silk acquires a negative charge.

Explanation:

• A glass rod when rubbed with silk, it acquires a positive charge. 
• It will repeal the positive charge, and attract the negative charge. 
• The glass rod attracted Y, which means the charge on Y is that of the opposite of the glass rod. So, the charge on Y is negative. 
• Y was rubbed with X, So, the charge on X will be opposite of Y. 
• The charge on Y is negative, so the charge on X is positive which is similar to that of a glass rod. 

So, the correct option is a glass rod. 

• Electric charge is acquired by the transfer of electrons. 
• The  SI unit of charge is Columb. 
• Electroscope is the device used to detect the electric charge.