Question 207: Properties of Matter

Question

A thin liquid film formed between a U-shaped wire and a light slider supports a weight of $$1.5 	imes {10^{ - 2}}\,\,N$$ (see figure). The length of the slider is $$30$$ $$cm$$ and its weight negligible. The surface tension of the  liquid film is

Accepted Answer

At equilibrium,
$$2Tl = mg$$
$$T = {{mg} \over {2l}} = {{1.5 	imes {{10}^{ - 2}}} \over {2 	imes 30 	imes {{10}^{ - 2}}}} = {{1.5} \over {60}}$$
$$ = 0.025\,N/m = 0.025Nm$$

Answer

$$0.0125\,\,N{m^{ - 1}}$$

Answer

$$0.1\,\,N{m^{ - 1}}$$

Answer

$$0.05\,\,N{m^{ - 1}}$$

Answer

$$0.025\,\,N{m^{ - 1}}$$

Properties of Matter

A thin liquid film formed between a U-shaped wire and a light slider supports a weight of $1.5 \times {10^{ - 2}}\,\,N (see figure). The length of the slider is 30 cm$ and its weight negligible. The surface tension of the liquid film is

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