7/25/2019 sci 1(16)

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44. Question: Why doesn?t the electric flament in an electric bulb burn up?

Answer: Firstly, because is made o tungsten which has a ery high melting

point !"4#$$%& whereas the temperature o the flament re'uired to glow is

only ()$$o%. *econdly, o+ygen is absent since the bulb is flled with an inert

gas which does not help in burning.

4. Question: Why does blotting paper absorb in-?

Answer: lotting paper has fne pores, which act li-e capillaries. When a

portion o blotting paper is brought in contact with in-, in- enters the pores

due to surace tension !capillary action li'uids& and is absorbed.

4/. Question: Why does a small iron sin- in water but a large ship 0oat?

Answer: 1he weight o water displaced by an iron ball is less than its own

weight, whereas water displaced by the immersed portion o a ship is e'ual

to its weight !Archimedes? 2rinciple&.