Two soap bubbles of radii $r_{1}$ and $r_{2}$ equal to 4 cm and 5 cm respectively are touching each other over a common surface $AB$ (shown in figure). Its radius will be [image:10_image69.emf]

Question

Dr. Abubacker · Accepted Answer

(d) $\frac{4S}{r_{1}} - \frac{4S}{r_{2}} = \frac{4S}{r}$
Or $\frac{1}{r} = \frac{1}{r_{1}} - \frac{1}{r_{2}} = \frac{1}{4} - \frac{1}{5} = \frac{1}{20}$ or $r = 20$ cm

Q. Two soap bubbles of radii $r_{1}$ and $r_{2}$ equal to 4 cm and 5 cm respectively are touching each other over a common surface $AB$ (shown in figure). Its radius will be

Explanation

Reviewed by Dr. Abubacker

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