Question

Which among the following is a formula for shear stress?

(a) τ = F*A

(b) τ = F/A

(c) τ = F/m

(d) τ = F*m

The question was asked in an international level competition.

I would like to ask this question from Shear Stress and Pressure Gradient topic in chapter Viscous Flow & Turbulent Flow of Fluid Mechanics

Answer 1

Right option is (b) τ = F/A

The explanation: Shear stress is defined as the force acting per unit area. Shear stresses arise from shear components(forces), which are pairs of equal and opposite forces. These forces act on the opposite side of the object.