Question

Stress in a solid body is defined as ___________ per unit area.

(a) external force applied

(b) strain

(c) pressure

(d) internal forces developed due to externally applied forces

I had been asked this question during a job interview.

My question is from Solids Mechanical Properties topic in section Mechanical Properties of Solids of Physics – Class 11

Answer 1

Correct choice is (d) internal forces developed due to externally applied forces

Explanation: When a force is applied on a solid body, internal forces develop inside it. Pressure is the external force per unit area while stress is the internal force per unit area. Note that pressure and stress aren’t the same.