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Question
If more air is pushed in a soap bubble, the pressure in it
Options
decreases
increases
remains same
becomes zero.
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Solution
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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