Start Free Mock LoginAlready registered? Login here

Physics - Fluid Question with Solution | TestHub

PhysicsFluidViscosityMedium2 minQB

PhysicsMediumsingle choice

A space 2.5 mm wide between two large plane surfaces is filled with oil. Force required to drag a very thin plate of area of one side $0.5 m^{2}$ just midway the surfaces at a speed of $0.5 m / sec$ is 1 N . The coefficient of viscosity in $kg / m$ -sec is

Options:

Answer:

Solution:

The plate is midway, leaving an oil film of thickness 1.25 mm on each side, and both films drag on the plate:

$F = 2 η A \frac{v}{d /2} = \frac{4 η A v}{d}$

With F = 1 N, A = 0.5 m2, v = 0.5 m/s, d = 2.5 mm:

$η = \frac{F d}{4 A v} = \frac{1 \times 2.5 \times 1 0 ^{- 3}}{4 \times 0.5 \times 0.5} = 2.5 \times 1 0^{- 3} kg/m - sec$

. Answer D.

Stream:JEESubject:PhysicsTopic:FluidSubtopic:Viscosity

⏱ 2mℹ️ Source: QB

Doubts & Discussion

Loading discussions...