Calculate the total angle of twist for a stepped shaft which is subjected to the torque (T) as shown in the figure below.
1
\(\frac{{TL}}{{\pi G{d^4}}}\)
2
\(\frac{{66TL}}{{\pi G{d^4}}}\)
3
\(\frac{{TL}}{{66G{d^4}}}\)
4
\(\frac{{36TL}}{{\pi G{d^4}}}\)