NEET 2022 · PhysicsExcess pressurePrevious Year Question
If a soap bubble expands, the pressure inside the bubble:
Answer: (A) decreases. Excess pressure inside a bubble = 4T/r.
- A.decreases✓
- B.increases
- C.remains the same
- D.is equal to the atmospheric pressure
Correct Answer
(A) decreases
Solution & Explanation
Excess pressure inside a bubble = 4T/r. As the bubble expands (r increases), the excess pressure — and hence the pressure inside — decreases.
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