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Name two events (other than an earthquake) which can cause tremors on the earth.
Answer
Two events other than earthquake which can cause tremors on earth are
- Nuclear explosions deep inside the earth
- Collision of meteors with earth
What is Earthing? Why it is done?
Answer
The process of transferring of charge from a charged object to the earth is called earthing.
It is done to prevent us from electric shocks in case of leakage of electric current.
During the construction of a building, the lightning conductor was left hanging in the air rather than connecting to the ground, by mistake. Would the lightning conductor be still effective? Explain.
Answer
No, the lightning conductor will not work.
In a lightning conductor, the top end receives the lightning and carries it to the ground, where the charges are discharged.
If the lower end was left hanging in the air rather than connecting to the ground, the charges won’t be discharged into the ground.
Hence, the lightning conductor won’t work.
Explain why a copper rod can not be charged if it is held by hand.
Answer
As soon as a copper rod gets charged, charges develop on it.
Since it is held by hand, the charges flow from the copper rod the the hand of the person holding it.
Human body is also a good conductor.
Since the person is connected to the ground, the charges flow from the hand to the ground causing.
Hence, a copper rod can not be charged if it is held by hand.
Do earthquakes occur all the time?
Answer
Yes, an earthquake occurs all the time all over the earth.
Most of the earthquakes are so mild that they are not felt by us.
Major earthquakes are less frequent but they are very dangerous.
