Question

Two soap bubbles have different radii but their surface tension is the same. Mark the correct statement

• A. Internal pressure of the smaller bubble is higher than the internal pressure of the larger bubble
• B. Pressure of the larger bubble is higher than the smaller bubble
• C. Both bubbles have the same internal pressure
• D. None of the above

Answer 1

Answer: (A)

Internal pressure of the smaller bubble is higher than the internal pressure of the larger bubble

$\Delta P=\frac{4T}{R}\therefore \Delta P\propto \frac{1}{R}$ ($T$ = constant)
Hence, the internal pressure of smaller bubble is larger than that of larger bubble.