Newton’s Law of Viscosity:
It says that the shear stress is proportional to the velocity gradient or shear strain rate.
Dynamic viscosity: Units 1 Poise =0.1 Pa-sec
μ = F h/VA = 𝑁 × 𝑚/𝑚/𝑠𝑒𝑐 × 𝑚2 = 𝑁𝑠𝑒𝑐/ 𝑚2 = Pa-sec F = μAV/ h
or Units of dynamic viscosity are Poise.
Kinematic viscosity (𝝂) :
It is defined as the ratio between the dynamic viscosity and density of the fluid.
ν = μ / ρ = 𝑁.𝑠𝑒𝑐/ 𝑚2 / 𝑘𝑔 / 𝑚3 = 𝑚2/ 𝑠𝑒𝑐
