Home
Class 12
PHYSICS
The ratio of surface tensions of mercury...

The ratio of surface tensions of mercury and water is given to be 7.5 while the ratio of their densities is 13.6.Their contact angles, with glass, are close to `135^@C` and `0^@`, respectively.It is observed that mercury gets depressed by an amount h in a capillary tube of radius `r_1`, while water rises by the same amount h in a capillary tube of radius `r_2`.The ratio `(r_1//r_2)`, is then close to : a) 4/5 b) 2/5 c) 3/5 d) 2/3

A

`2/5`

B

`2/3`

C

`4/5`

D

`3/5`

Text Solution

Verified by Experts

The correct Answer is:
A
`h=(2T cos theta)/(rho gr)`
So, `h=(2T_(Hg) | cos(135^(@))|)/(rho_"Hg"). G.r_(1)) =(2T_("water").cos0^(@))/(rho_("water").g.r_(2))`
`rArr r_(1)/r_(2) =(T_(Hg))/(T_("water")) (|cos135^(@)|)/(cos 0^(@)) xx (rho_("water"))/(rho_(H//g)) = 7.5 xx 1/sqrt(2) xx 1/13.6 ~=0.4`
Promotional Banner

Topper's Solved these Questions

  • JEE MAIN REVISION TEST -14

    VMC MODULES ENGLISH|Exercise PHYSICS (SECTON 2)|5 Videos

  • JEE MAIN REVISION TEST - 7|JEE - 2020

    VMC MODULES ENGLISH|Exercise Physics (Section -2) (Numerical Value Type)|5 Videos

  • JEE MAIN REVISION TEST -17 (2020)

    VMC MODULES ENGLISH|Exercise PHYSICS|25 Videos

Similar Questions

Explore conceptually related problems

If 'M' is the mass of water that rises in a capillary tube of radius 'r', then mass of water which will ris in a capillary tube of radius '2r' is :

Mercury sticks to the walls of the capillary tube.

mass m of a liquid rises inside a capillary of radius r . The mass of fluid that rises when a capillary of radius 2r is used is

Water rises to a height h when a capillary of radius r is dipped in water. For another capillary of radius 2r dipped in water, it rises to the height

Water rises to a height h in a capillary tube of cross-sectional area A. the height to which water will rise in a capillary tube of cross-sectional area 4A will be

Water rises to a height h in a capillary tube of cross-sectional area A. the height to which water will rise in a capillary tube of cross-sectional area 4A will be

Figure shows a capillary tube of radius r dipped into water. If the atmosphere pressure is P_0 , the pressure at point A is

"The angle of contact of mercury with glass is obtus, while the water with glass is acute." Why?

Water rises in a glass capillary tube, but descends if the bore of the capillary tube is coated with paraffin wax. Why ?

The liquid in the capillary tube will rise if the angle of contact is