Science
Which of the following cannot be charged easily by friction?
- A plastic scale
- A copper rod
- An inflated balloon
- A woollen cloth.
Answer
A copper rod.
Reason — When an object is charged by friction, charges develop on the two materials involved in friction. Copper being a good conductor, allows the charges to move easily and redistributes the excess charges quickly and doesn't retain a significant charge through friction. Therefore, it's difficult to charge a copper rod through friction.
Related Questions
When a glass rod is rubbed with a piece of silk cloth, the rod
- and the cloth both acquire a positive charge.
- becomes positively charged while the cloth has a negative charge.
- and the cloth both acquire a negative charge.
- becomes negatively charged while the cloth has a positive charge.
Write T against true and F against false in the following statements.
(a) Like charges attract each other. (T/F)
(b) A charged glass rod attracts a charged plastic straw. (T/F)
(c) Lightning conductors cannot protect a building from lightning. (T/F)
(d) Earthquakes can be predicted in advance. (T/F)
Sometimes, a crackling sound is heard while taking off a sweater during winter. Explain.
Explain why a charged body loses its charge if we touch it with our hand.