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Following are precautions one must take in case a storm is accompanied by lightning. (i) Do not take shelter under a tree. (ii) Do not take shelter under an umbrella with a metallic end. (iii) Do not take shelter in open garages, storage sheds, etc. (iv) Do not take shelter in a bus in the open. Which one of these is not correct? (a) (i) (b) (ii) (c) (iii) (d) (iv)

(d) (iv) Do not take shelter in a bus in the open Buses are made up of metals from outside and hence when the lighting strikes the bus it would... View Article

Figure shows a child blowing air with a straw near the opening of another straw which has its other end in a soft drink bottle. It was observed that the level of the soft drink in the straw rises up as soon as air is blown over its open end. Which one of the following best explains the reason for the rise in the level of the drink? (a) The blowing of air decreases pressure over the opening of the straw. (b) The straw of the soft drink bottle collapses when air is blown over its open end. (c) The blowing of air warms up the air inside the straw. (d) The blowing of air increases the pressure on the surface of the soft drink in the bottle.

The answer is (a) Blowing of air decreases pressure over the opening of the straw. Decreased pressure over the opening of the straw makes the... View Article