Ans. The tremors produce waves on the surface of the earth. These are called seismic waves.
Ans. Lightning Conductor is a device used to protect buildings from the effect of lightning.
Ans. An earthquake is a sudden shaking or trembling of the earth lasting for a very short time. It is caused by a disturbance deep inside the earth’s crust.
Ans. Although, we know for sure what causes an earthquake, it is not yet possible to predict when and where the next earthquake might occur.
Ans. Tremors on the earth can also be caused when a volcano erupts, or a meteor hits the earth, or an underground nuclear explosion is carried out.
Ans. The nature of charge on the other object will be negative. This is because like charges repel each other and unlike charges attract each other.
Ans. When we touch a charged body with our hand, then the electric charge present on it flows to the earth through our hand and body. That is why a charged body loses its charge if we touch it with our hand.
Ans. Really destructive earthquakes have magnitudes higher than 7 on the Richter scale. Both Bhuj and Kashmir earthquakes had magnitudes greater than 7.5.
Ans. When a plastic comb is rubbed with dry hair, it acquires a small charge due to friction. The electrically charged comb then exerts an electric force on the tiny pieces of paper and attracts them.
Ans. In 1752 Benjamin Franklin, an American scientist, showed that lightning and the spark from your clothes are essentially the same phenomena.
Ans. During a thunderstorm, there is danger of lightning striking the tree and burning it up. This lightning can also pass through the body of the person standing under the tree and may kill him. Therefore, it is not wise to stand under a tree during a thunderstorm.
Ans. The aluminium foil strips receive the same charge from the charged refill through the paper clip. The strips carrying similar charges repel each other and they become wide open.
Ans. When plates brush past one another, or a plate goes under another due to collision, they cause disturbance in the earth’s crust. It is this disturbance that shows up as an earthquake on the surface of the earth.
Ans. Carrying umbrella is not a good idea at all during thunderstorms because lightning may strike the top end of the metal rod of umbrella and harm us.
Ans. When we take off a woolen (or synthetic) sweater, it rubs against our shirt. Due to rubbing, opposite electric charges develop on them, which attract each other. The discharge of these electric charges produces tiny sparks of light as well as crackling sound.
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