A metal block of base area `0.2m^(2)` is connected to a 0.02 kg mass via a string that passes over an ideal pulley as shown in figure.A liquid film of thickness 0.6 mm is placed between the block moves to the right with a constant speed of 0.17 m/s The coefficient of viscosity of liquid is .......

Options

A. `3.45xx10^(3)Pa*s`
B. `3.45xx10^(-2)Pa*s`
C. `3.45xx10^(-3)Pa*s`
D. `3.45xx10^(2)Pa*s`

Answer

c

Explanation

Viscous force , `F=etaA(DeltaV)/(Deltax)`
`thereforeeta=(FDeltax)/(ADeltaV)`
`=(mgDeltax)/(ADeltaV)`
`=(0.2xx9.8xx6xx10^(-4))/(0.2xx0.17)`
`thetaeta=34.58xx10^(-4)`
`thereforeeta=3.45xx10^(-3)Pa*s`