MCQ
A soap bubble in vacuum has a radius of $3 \,cm$ and another soap bubble in vacuum has a radius of $4 \,cm$. If the two bubbles coalesce under isothermal condition, then the radius of the new bubble is ....... $cm$
- A$2.3$
- B$4.5$
- ✓$5 $
- D$7$
✓
Answer
Correct option: C.
$5 $
c
(c) $r = \sqrt {r_1^2 + r_2^2} = \sqrt {9 + 16} = 5\;cm$
(c) $r = \sqrt {r_1^2 + r_2^2} = \sqrt {9 + 16} = 5\;cm$
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