Question

In a U-tube, the radii of two columns are respectively r₁ and r₂. When a liquid of density ρ(θ = 0°) is filled in it, a level difference of h is observed on two arms, then the surface tension of the liquid is ______.

विकल्प

• `(rhoghr_1r_2)/(2(r_2 - r_1))`

• `hrhog(r_2 - r_1)`

• `(hrhog(r_2 - r_1))/2`

• `(hrhog)/(2(r_2 - r_1))`

Answer 1

In a U-tube, the radii of two columns are respectively r₁ and r₂. When a liquid of density ρ(θ = 0°) is filled in it, a level difference of h is observed on the two arms, then the surface tension of the liquid is `underlinebb((rhoghr_1r_2)/(2(r_2 - r_1)))`.

Explanation:

ρgh = 2T

`1/h = 1/r_1 - 1/r_2`

`1/h = ((r_2 - r_1))/(r_1r_2)`

`h = (r_1r_2)/(r_ 2 - r_1)`

So, `(rhog(r_2 - r_1))/(r_1 xx r_2)` = 2T