Assertion (A): Most of actual systems are non-linear.

Reason (R): Non linearity may be due to saturation, dead zone, square law etc.

Assertion (A): Temperature control of the passenger compartment of car uses both feed forward and feedback controls.

Reason (R): Feed forward control gives corrective action before the disturbance affects the output and feedback control applies corrective action after output changes.

In a lag network the input frequency is 100 f_c where f_c is critical frequency. The voltage gain is

The shape of torque-speed curve of a two phase servo- motor mostly depends on

Transfer functions of even complicated components can be found by frequency response tests.