If a soap bubble expands, the pressure inside the bubble :

1. is equal to the atmospheric pressure

2. decreases

3. increases

4. remains the same

Doubtly Asked 30 Oct 2026 NEET UG 2022 Practice test neet Save WhatsApp Report

1 answer

Best answer

Answer: 2. decreases

Excess pressure inside a soap bubble is \(\Delta P=\dfrac{4S}{r}\), so it is inversely proportional to the radius.

When the bubble expands, \(r\) increases, so the excess pressure, and hence the inside pressure, decreases. Option (2) is correct.

The pressure inside is always higher than atmospheric, so (1) is wrong.

Doubtly AI · 30 Oct 2026 AI-generated · not yet verified Report

Was this answer helpful?