MCQ
A bubble of $8$ mm diameter is formed in the air. The surface tension of soap solution is $30$ dynes/cm. The excess pressure inside the bubble is ........ $dynes/cm^2$
- A$150$
- ✓$300$
- C$3 × 10^{-3}$
- D$12$
✓
Answer
Correct option: B.
$300$
b
(b) $\Delta P = \frac{{4T}}{r} = \frac{{4 \times 30}}{{0.4}} = 300\;dyne/c{m^2}$.
(b) $\Delta P = \frac{{4T}}{r} = \frac{{4 \times 30}}{{0.4}} = 300\;dyne/c{m^2}$.
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