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PhysicsMediumNumerical2023 · 11 Apr Shift 2

Q10.The surface tension of soap solution is 3. 5 × 10−2 N m−1 . The amount of work done required to increase the radius of soap bubble from 10 cm to 20 cm is _____ ×10−4 J . (take π = 227 )

What This Question Tests

This question tests the calculation of work done to increase the size of a soap bubble, which involves understanding the surface area of a bubble (two surfaces) and the surface tension formula.

Concepts Tested

Surface energyWork done against surface tensionSurface area of bubble

Formulas Used

W = T ΔA

A_bubble = 2 * 4πR^2

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