A frame made of metallic wire enclosing a surface area A is covered with a soap film. If the area of the frame of metallic wire is reduced by 25%, the energy of the soap film will be changed byA. 1B. 0.75C. 0.5D. 0.25

A frame made of metallic wire enclosing a surface area A is covered wi

1.	A frame made of metallic wire enclosing a surface area A is covered with a soap film. If the area of the frame of metallic wire is reduced by 25%, the energy of the soap film will be changed byA. 1B. 0.75C. 0.5D. 0.25
Answer» Correct Answer - D Surface energy = Surface tension `xx` Surface area `E = T xx 2A` New surface energy, `E_(1) = T xx 2((A)/(4)) = T xx (A)/(2)` % decrease in surface energy `= (E xx E_(1))/(E) xx 100 = (2TA - TA//2)/(2TA) xx 100 = 75%`

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A frame made of metallic wire enclosing a surface area A is covered with a soap film. If the area of the frame of metallic wire is reduced by 25%, the energy of the soap film will be changed byA. 1B. 0.75C. 0.5D. 0.25

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