For the circuit in Fig., write the state equations using v_c and i_L as state variables.

The circuit of Fig. represents a

In the circuit of Fig., the value of the voltage source E is

Let u(t) be the unit step function. Which of the waveforms in Fig.(a) -(d) corresponds to the convolution of $$\left[ {u\left( t \right)\, - \,u\left( {t\, - \,1} \right)} \right]$$ with $$\left[ {u\left( t \right)\, - \,u\left( {t\, - \,2} \right)} \right]$$ ?