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Two spherical soap bubbles of radii r1 and r2 in vacuum combine under isothermal conditions. The resulting bubble has a radius equal to:
- r1r2/(r1 + r2)
- √(r1r2)
- √(r1² + r2²)
- (r1 + r2)/2
Correct answer: √(r1² + r2²)
Solution
The correct option reflects the geometric relationship between the radii of the two bubbles when they combine, as the resulting bubble's radius is determined by the Pythagorean theorem, which accounts for the contributions of both original radii.
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