A shaft of diameter D is subjected to a twisting moment of T and

A shaft of diameter D is subjected to a twisting moment of T and
| A shaft of diameter D is subjected to a twisting moment of T and Bending moment of M respectively. If the maximum bending stress is equal to maximum shear stress developed. Then M is equal to

A. <span class="math-tex">\(\frac T2\)</span>

B. T

C. 2T

D. 4T

Please scroll down to see the correct answer and solution guide.

Right Answer is: A

SOLUTION

Concept:

Maximum Bending stress due to bending moment:

\({σ _b} = \frac{{32M}}{{\pi {d^3}}}\)

Maximum Shear stress due to twisting moment/ torque:

\(τ = \frac{{16T}}{{\pi {d^3}}}\)

Calculation:

Given:

Maximum bending stress = Maximum shear stress

σb = τ  

\(\frac{{32M}}{{\pi {d^3}}}\) = \( \frac{{16T}}{{\pi {d^3}}}\)

Hence, \(M = \frac T2\)