Question

A horizontal force of 1N is required to move a metal plate of area 10^-2m^2 with a velocity of 2×10^-2 m/s . when it rest on a layer of oil 1.5×1₩^-3 m thick. find the coefficient of viscosity of oil​

Answer 1

Answer:

F=1N,A=10−2m2,v0=2×10−2m/s,y=1.5×10−3m

Velocity gradient, dydv=(1.5×10)−3(2×10−2)=340s−1

Viscous force, F=ηdydv

∴ The coefficient of viscosity is

η=A(dydv)F=(10−2m2)(40/3s−11N=430=7.5Pa.s