Question

The angle between the two lines (x and y direction) is called as ___________

(a) viscous layer

(b) strain

(c) stress

(d) velocity vector

The question was posed to me during an interview for a job.

The query is from Angular Velocity, Vorticity, Strain in division Aerodynamics – Fundamental Principles and Equations of Aerodynamics

Answer 1

The correct choice is (b) strain

The explanation: Strain is defined as the change in angle between the two lines in a flow field. Suppose Δθ1 and Δθ2 are the angles between the two lines in a flow field. Therefore, strain can be given by –  Strain= Δθ2 – Δθ1.