What is the dimensional formula for viscosity ?
Answers
Answer:
Mathematically, Coefficient of viscosity (η)= Fr/Av ——- F= tangential Force, Area, r= distance between the layers, v= velocity. Dimensional Formula of Force = M1L1T-2.
Dimensional Formula of Viscosity
The dimensional formula of Viscosity (η) is given by,
M1 L-1 T-1
Where,
M = Mass
L = Length
T = Time
Derivation
Viscosity = Tangential Force × Distance between layers × [Area × Velocity]-1 . . . . . (1)
Since, Tangential Force = M × a = M × [L T-2]
∴ The dimensional formula of Tangential Force = M1 L1 T-2 . . . . (2)
And, the dimensions of area and velocity = M0 L2 T0 and M0 L1 T-1 . . . . (3)
On substituting equation (2) and (3) in equation (1) we get,
Viscosity = Force × [Area × Velocity]-1 × Distance between layers
Or, η = [M1 L1 T-2] × [M0 L2 T0]-1 × [M0 L1 T-1]-1 × [M0 L1 T0] = [M1 L-1 T-1].
Therefore, viscosity is dimensionally represented as [M1 L-1 T-1].