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6. Name the scale on which the destructive energy of an earthquake is measured, An earthquake measures 3 on this scale., Would it be recorded by a seismograph? Is it likely to cause much damage?, , Ans; The destructive energy of an earthquake is measured on a Richter scale. A seismograph can measure an earthquake of, magnitude 3 on Richter scale. Such an earthquake is of low intensity and may not cause any damage., , 7, Suggest three measures to protect ourselves from lightning,, Ans; Three measures to protect ourselves from lightning are given below:, * Squat low on the ground if in an open field., * Ifin a forest, take shelter under shorter trees instead of tall trees., * Contact with telephone cords, metal pipe, or electrical wires should be avoided,, , 8. Explain why a charged balloon is repelled by another charged balloon whereas an uncharged balloon is attracted by another, charged balloon?, Ans: Both the charged balloons have the same charges and so they repel each other. An uncharged balloon that is brought near a, charged balloon picks up some opposite charge and this attracts it to the charged balloon., , ‘ 9. Describe with the help of a diagram an instrument which can be used to detect a charged body., , Ans: An electroscope is the instrument that can be used to detect a charged body. A simple electroscope can be, created easily. Take an empty bottle or beaker. Place a cardboard on the mouth of the bottle that is slightly larger in, size. Make a hole in the cardboard. Take a metal paper clip and open it out. Take two strips of aluminium foil and, hang them on one end of the paper clip. Hang the paper clip through the hole in the cardboard into the bottle. Touch, a charged object to the outer end of the clip. The strips become wide open as they will have the same charge as the, , object. This is because when the objects are carrying similar charges, they repel each other and become wide open., , If you touch the clip with your hand, the strips return to their original state as charge is transferred to the Earth, through us., , 10. List three states in India where earthquakes are more likely to strike., , Ans: Three states in India where earthquakes are more likely to strike are Jammu and Kashmir, North-Eastern states such as Assam,, and Rajasthan., , , , 11. Suppose you are outside your home and an earthquake strikes. What precaution would you take to protect yourself?, , Ans: If an earthquake strikes when we are outside our home, we should find a clear spot that is away from buildings, trees, and power, lines, and drop to the ground. If inside a car or a bus, we should not come out of the vehicle. We should ask the driver to drive slowly, to a clear spot, and come out of the vehicle only when the tremors stop., , 12. The weather department has predicted that a thunderstorm is likely to occur on a certain day. Suppose you have to go out on, , that day. Would you carry an umbrella? Explain., , Ans: Carrying umbrella is not a good idea at all during thunderstorms. If it has a metal tip, it can be dangerous. It also makes us a, target for the lightning to strike.