Home
Class 11
PHYSICS
Shown in the figure is a container whose...

Shown in the figure is a container whose top and botoom diameters are D and d respectively. At the bottom of the container, there is a capillary tube of outer radius b and inner radius a.
The volume flow rate in the capillary is Q. If the capillary is removed the liquid comes out with a velocity of `v_0`. The density of the liquid is given as `rho`. Calculate the coefficient of viscosity `eta`.

Text Solution

Verified by Experts

The correct Answer is:
A, B, D

KEY CONCEPT: When the tube is not there, using Bernoulli's theorem
`P+P_0+1/2rhov_1^2+rhogH=1/2rhov_0^2+P_0`
`impliesP+rhogH=1/2rho(v_0^2-v_1^2)`
But according to equation of continuity
`v_1=(A_2v_0)/(A_1)`
`:.P+rhogH=1/2rho[v_0^2-(A_2/A_1v_0)^2]`
`P+rhogH=1/2rhov_0^2[1-(A_2/A_1)^2]`
Here, `P+rhogH=DeltaP`
According to Poisseuille's equation
`Q=(pi(DeltaP)a^4)/(8etal)=eta=(pi(DeltaP)a^4)/(8Ql)`
`:. eta=(pi(P+rhogH)a^4)/(8Ql)=(pi)/(8Ql)xx1/2rhov_0^2[1-(A_2/A_1)^2]xxa^4`
Where `A_2/A_1=d^2/D^2`
`eta=(pi)/(8Ql)xx1/2rhov_0^2[1-d^4/D^4]xxa^4`
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • MECHANICAL PROPERTIES OF MATTER AND FLUIDS

    SUNIL BATRA (41 YEARS IITJEE PHYSICS)|Exercise Subjective Problems|1 Videos
  • LAWS OF MOTION

    SUNIL BATRA (41 YEARS IITJEE PHYSICS)|Exercise JEE Main And Advanced|79 Videos
  • MOMENTUM & IMPULSE

    SUNIL BATRA (41 YEARS IITJEE PHYSICS)|Exercise JEE Main And Advanced|30 Videos

Similar Questions

Explore conceptually related problems

Shown in the figure is a container whose top and bottom diameters are D and d respectively At the bottom of the container these is a cappillary tube of outer radius b and inner radius a. the volume flow rate in the capillary is Q. if the capillary is removed the liquid comes out with a velocity of v_(0) . The density of the liquid is given as calculate the coefficient of viscosity eta (given pia^(2)=10^(-6)m^(2) and (a^(2))/(l)=2xx10^(-6)m ]

When a capillary tube is dipped into a liquid, the liquid neither rises nor falls in the capillary.

Knowledge Check

  • The rate of flow of a liquid through a capillary tube is

    A
    directly proportional to the length of tube.
    B
    inversely proportional to the difference of pressure between the ends of the tube.
    C
    directly proportional to the `4^(th)` power of the radius of the tube.
    D
    independent of the nature of the liquid.
  • If a liquid does not wet the material of a capillary tube, then the liquid in it

    A
    rises
    B
    falls
    C
    neither rises nor falls
    D
    starts freezing .
  • The rise of a liquid in a capillary tube is due to:

    A
    osmosis
    B
    surface tension (c) viscosity
    C
    viscosity
    D
    diffusion
  • Similar Questions

    Explore conceptually related problems

    The rate of flow of water in a capillary tube of length l and radius r is V. The rate of flow in another capillary tube of length 21 and radius 2 r for same pressure difference would be

    The rise of a liquid in a capillary tube is due to :

    A capillary tube is dipped in a water container , so that loss in weight of the capillary tube is

    A liquid of density 900(kg)/(m^(3)) is filled in a cylindrical tank of upper radius 0.9 m and lower radius 0.3 m A capillary tube of length 1 is attached at the bottom of the tank as shown in fig. The capillary has outer radius 0.002 m and inner radius a. When pressure P is applied at the top of the tank volume flow rate of liquid is 8xx10^(-6)(m^(3))/(s) and if capillary tube is detached, the liquid comes out from the tank with a velocity 10(m)/(s) . then the coefficient viscosity of liquid is (pia^(2)=10^(-6)m^(2)a^(2))/(l=2xx10^(-6)m) .

    A capillary tube of the radius r is immersed in water and water rise in it to a height H. Mass of water in the capillary tube is m. If the capillary of radius 2r is taken and dipped in water, the mass of water that will rise in the capillary tube will be