Water rises to a height of 10 cm. in a certain capillary tube. If in the same tube, level of Hg is depressed by 3.42 cm., compare the surface tension of water and mercury. Sp. Gr. Of Hg is 13.6 the angle of contact for water is zero and that for Hg is `135^@.`

Options

A. `13 : 2`
B. `5 : 16`
C. `16 : 5`
D. `2 : 13`

Answer

D

Explanation

Given, `h_(1)=10cm, h_(2)=3.42cm`
`theta_(2)=135 and d_(2)=13.6 "gcc"^(-1)`
`"Here" (T_(1))/(T_(2))=(h_(1)d_(1))/(h_(2)d_(2))(cos theta_(2))/(cos theta_(1))Rightarrow (T_(1))/(T_(2))=(10xx1)/(3.43xx13.6)(cos 135^(@))/(cos 45^(@)) Rightarrow (T_(1))/(T_(2))=(2)/(13)`