MCQ
Two soap bubbles of radii $3r$ and $4r$ in contact with each other. The radius of curvature of the interface between bubbles is
- A$3r$
- B$3.5r$
- ✓$12r$
- D$r$
✓
Answer
Correct option: C.
$12r$
c
${r_{common}}\, = \,\frac{{{r_1}{r_2}}}{{{r_2} - {r_1}}} = \frac{{12r}}{1} = 12r$
${r_{common}}\, = \,\frac{{{r_1}{r_2}}}{{{r_2} - {r_1}}} = \frac{{12r}}{1} = 12r$
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