GATE Electrical Engineering (EE) 2013 Solved Paper

The open-loop transfer function of a dc motor is given as:  $\frac{\mathit{\omega }\left(\mathit{s}\right)}{{\mathit{V}}_{\mathit{a}}\left(\mathit{s}\right)}=\frac{10}{1+10\mathit{s}}$ . When connected in feedback as shown below, the approximate value of K_a that will reduce the time constant of the closed-loop system by one hundred times as compared to that of the open-loop system is