Question

When we remove polyester or woolen clothes in the dark, we can see spark and crackling sound, these are due to?
(A) Static electricity
(B) Current electricity
(C) Reflection of light
(D) Refraction of light

Answer 1

Hint : During removing wool or polyester clothes there is friction between body clothes and wherever there is friction static charges comes into account. Friction is a source of heat that makes electrons move.

Complete step by step solution:
The sparking sound which comes from polyester and woolen clothes is an example of small static electricity. The static electricity builds as a result of friction between fabric and another surface, either the skin or the carpet. As the fabric is removed from the skin , the static jumps between the cloth and the skin making a cracking sound.
The sparks and cracking sounds are made by electrical discharges of thousands and thousands of volts. The sound you are probably referring to is the sound generated by the discharge of static electricity. It is the same sound that is caused by lightning and is also a static electrical discharge. It also doesn't just happen with synthetics.
The same electrical discharge can happen in humid or moist air. However, the fabric is more likely to pick up a charge in dry air.


Thus we can say that the option (A) is correct

Note:
When negative and positive charges are rubbed together then it produces tiny parks of light. Static charges are always developed when rubbing two bodies , there are two ways to charge the body: charging by friction and charging by induction. The same crackling sound and spark can also be seen on some larger ground in transmission lines which is called CORONA discharge.