In the system whose signal flow graph is shown in the figure, $${{U_1}\left( s \right)}$$ and $${{U_2}\left( s \right)}$$ are inputs. The transfer function $${{Y\left( s \right)} \over {{U_1}\left( s \right)}}\,$$ is

The transfer function of a system is given by $${{{V_0}\left( s \right)} \over {{V_i}\left( s \right)}} = {{1 - s} \over {1 + s}}$$

Let the output of the system be $${v_0}\left( t \right) = {v_m}\sin \left( {\omega t + \phi } \right)$$ for the input $${v_i}\left( t \right) = {v_m}\sin \left( {\omega t} \right).$$ Then the minimum and maximum values of ϕ (in radians) are respectively

For a system having transfer function $$G\left( s \right) = {{ - s + 1} \over {s + 1}},$$ a unit step input is applied at time $$t=0.$$ The value of the response of the system at $$t=1.5$$ sec (round off to three decimal places) is __________.

The logical gate implemented using the circuit shown below where $${V_1}$$ and $${V_2}$$ are inputs (with $$0$$ $$V$$ as digital $$0$$ and $$5$$ $$V$$ as digital $$1$$) and $${V_{OUT}}$$ is the output is