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प्रश्न
If more air is pushed in a soap bubble, the pressure in it
विकल्प
decreases
increases
remains same
becomes zero.
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उत्तर
Excess pressure inside a bubble is given by: \[P = \frac{4T}{r}\].
When air is pushed into the bubble, it grows in size. Therefore, its radius increases. An increase in size causes the pressure inside the soap bubble to decrease as pressure is inversely proportional to the radius.
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