When a shaft is subjected to combined twisting moment (T) and bending moment (M), the equivalent bending moment is equal to
1
\( \sqrt {{M^2} + {T^2}} \)
2
\(\sqrt {{M^2} + 4 {T^2}} \)
3
\(\sqrt {4{M^2} + {T^2}} \)
4
\(\frac{1}{2}\left\{ {M + \sqrt {{M^2} + {T^2}} } \right\}\)