A two-port device is defined by the following pair of equations:
$${i_1} = 2{v_1} + {v_2}$$ and $${i_2} = {v_1} + {v_2}$$
Its impedance parameters $$\left( {{z_{11}},\,\,{z_{12}},\,\,{z_{21}},\,\,{z_{22}}} \right)$$ are given by

A voltage wafeform $$v\left( t \right) = 12\,{t^2}$$ is applied across a $$1$$ $$H$$ inductor for $$t \ge 0,$$ with initial current through it being zero. The current through the inductor for $$t \ge 0$$ is given by:

Predict the current $${\rm I}$$ in Fig. in response to a voltage of $$20\angle {0^0}\,V.$$ The impedance values are given in $$ohms.$$ Use Thevenin's theorem.

Instrument transformers are known to introduce magnitude and phase errors in measurements. These are primarily due to