A U-shaped wire is dipped in a soap solution, and removed. The thin soap film formed between the wire and the light slider supports a weight of 1.5 × 10–2 N (which includes the small weight of the slider). The length of the slider is 30 cm. What is the surface tension of the film ?

Asked by Pragya Singh | 1 year ago |  73

1 Answer

Solution :-

The maximum weight the film can support, W = 1.5 × 10-2 N

Length of the slider, l = 30 cm = 0.3 m

Total length of liquid film, l = 2 x 30 cm = 60 cm = 0.6 m because the liquid film has two surfaces.

Surface tension, 

T = \( \dfrac{F}{I}\) =1.5 x 10-2 N/0.6m 

=2.5 x 10-2 Nm-1

Answered by Abhisek | 1 year ago

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