When a shaft is subjected to combined twisting moment (T) and bending moment (M), the equivalent twisting moment is equal to
- A. $1/2 [M + \sqrt{M²+T²}]$
- B. $\sqrt{M²+4T^2}$
- C. $\sqrt{4M^2+T²}$
- D. $\sqrt{M²+T²}$
Answer: D. $\sqrt{M²+T²}$
Explanation: Equivalent twisting moment $T_e = \sqrt{M²+T²}$.