Physics · Geometrical Optics

JEE Main 2025 — 22 January, Morning Shift — Question 61

Two soap bubbles of radius 2 cm and 4 cm , respectively, are in contact with

each other. The radius of curvature of the common surface, in cm , is $\qquad$ .

Answer: 4

Numerical answer — enter this value.

$\quad r=\frac{r_{1} \cdot r_{2}}{r_{1}-r_{2}}=\frac{2 \cdot 4}{4-2}=4 \mathrm{~cm}$

Answer key and solution verified before publishing.

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