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(a) A comb run through one's hair attractssmall bitsof paper. Why ? What happens if the hairare wet or if it a rainy day? (b) Ordinary rubber is an insulator. But the specailrubbertyresof aircrafts are made slightly conducting. Why is this neccessary? (c) Vehicles carrying inflammable materialsusually have metallicropestouchingthe groundduringmotion. Why ? (d) A bird perches on a bare high power line, and nothinghappensto the bird. A manstandingon the groundtouches the same line and getsa fatal shock. Why? |
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Answer» Solution :(a) This is because the comb gets chargedby friction. If the hairare wet, or if it is a rainy day, frictionbetween the hairand the combreduces. The comb does not getcharged, and it will notattract small bits of paper. (b) The specail rubbertyresof AIR crafts are madeslightly condutingso thatelectricity generatedon accountof frictionbetween the tyresand the runway goes to EARTH. (c) When a vehiclemoves, its body gets charged on account of friction betweenthe tyres and the ROAD. Themetallic ropesfrom the vehicletouchingthe groundenable theaccumulatedcharge on accountof frictionbetweenthe tyresand the road = The metallic ropesfrom the vehicle touchingthe groundenable the accumulated charges to flow to earth. Thiswouldotherwisebe hazordous to the INFLAMMABLEMATERIALS. (d) Whena birdperches on singlebare high powerline, NOTHING happens to him as nocurrentflowsthrough his body. Currentflowsthorugh his bodyresulting in a fatal shock. |
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