A lead compensator network includes a parallel combination of 'R' and 'C' in the feed-forward path. If the transfer function of the compensator is $${G_C}(s) = {{s + 2} \over {s + 4}}.$$ The value of RC is ____

The transfer function of a compensator is given as $${G_C}(s) = {{s + a} \over {s + b}}.$$

$${G_C}(s)$$ is a lead compensator if

The transfer function of a compensator is given as $${G_C}(s) = {{s + a} \over {s + b}}.$$

The phase of the above lead compensator is maximum at

A unity negative feedback closed loop system has a plant with the transfer function $$G(s) = {1 \over {{s^2} + 2s + 2}}$$ and a controller $${G_c}(s)$$ in the feed forward path. For a unit set input, the transfer function of the controller that gives minimum steady sate error is