When a shaft is subjected to combined twisting moment (T) and bending moment (M), then the equivalent twisting moment is equal to
A
$$\frac{1}{2}\sqrt {{{\text{M}}^2} + {{\text{T}}^2}} $$
B
$$\sqrt {{{\text{M}}^2} + {{\text{T}}^2}} $$
C
$$\frac{1}{2}\left( {{\text{M}} + \sqrt {{{\text{M}}^2} + {{\text{T}}^2}} } \right)$$
D
$${\text{M}} + \sqrt {{{\text{M}}^2} + {{\text{T}}^2}} $$
Correct Answer: $$\sqrt {{{\text{M}}^2} + {{\text{T}}^2}} $$