Water rises in a capillary tube to a certain height such that the upward force due to surface tension is balanced by ` 75 xx 10 ^(-4) `N force due to the weight of the liquid. If the surface tension of water is ` 6 xx 10 ^( -2) Nm^(-1) ` the inner circumference of the capillary must be: (angle of contact is zero)

Options

A. `1.25xx10^(-2) m`
B. `0.50xx10^(-2) m`
C. `6.5xx10^(-2) m`
D. `12.5xx10^(-2) m`

Answer

D

Explanation

`6xx10^(-2)xx" circumference "=Force`
`therefore" ""Circumference"=(75xx10^(-4))/(6xx10^(-2))=12.5xx10^(-2)m`