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A small soap bubble of radius 4 cm is trapped inside another bubble of radius 6 cm without any contact. Let P2 be the pressure inside the inner bubble and P0 the pressure outside the outer bubble. Radius of another bubble with pressure difference P2 - P0 between its inside and outside would be - [JEE-Main On line-2018]
- 6 cm
- 12 cm
- 4.8 cm
- 2.4 cm
Correct answer: 2.4 cm
Solution
The pressure difference between the inside and outside of a bubble is inversely related to its radius, according to the Young-Laplace equation. Given the pressure difference between the inner bubble and the external pressure, the radius of the new bubble can be calculated, resulting in a radius of 2.4 cm.
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