Question

The lower end of a capillary tube is immersed in mercury. The level of mercury in the tube is found to be 2 cm below the outer level. If the same tube is immersed in water, up to what height will the water rise in the capillary ?

Answer 1

Correct Answer - C
`h_(Hg)=(2T_(Hg)costheta_(Hg))/(r rho_(Hg)g)`
`h_2=(2T_wcostheta_w)/(r rho_wg)`
where the symbols have their usual meanigns.
`h_w/h_(Hg)=h_2/h_(Hg)=rho_(Hg)/rho_wxx(costheta)/(costheta_(Hg))`
`=(0.075/0.465)xx(13.6)xx((cos 0^@)/(cos40^@))`
`rarr h_w=2xx(2.9)=5.8cm`