The ratio $\frac{\tau _{1}}{\tau _{2}}$ is

Question

A 3 – meter long steel cylindrical shaft is rigidly held at its ends. A pulley is mounted on the shaft at 1 meter from one end; the shaft is twisted by applying torque on the pulley. The maximum shearing stresses developed in 1 m and 2m lengths are respectively $\tau _{1}$ and $\tau _{2}$. The ratio $\frac{\tau _{1}}{\tau _{2}}$ is

(a) 1/2           (b) 1        (c) 2        (d) 4