In the circuit shown in figure calculate and sketch the wave form of current $$'i'$$ over one period of the i/p voltages. Assume the diodes to be ideal

An ideal op-amp is used to make an inverting amplifier. The two input terminals of the op-amp are at the same potential because

Which of the following figure(s) represent valid root loci in the $$s$$ - plane for positive $$K?$$ Assume that the system has transfer function with real coefficient.

A unity feedback system has the open loop transfer function $$G\left( s \right) = {1 \over {\left( {s - 1} \right)\left( {s + 2} \right)\left( {s + 3} \right)}}$$
The Nyquist plot of $$G$$ encircle the origin