The input resistance $${R_{IN}}\left( { = {V_x}/{I_x}} \right)$$ of the circuit in the figure is

In the Schmitt trigger circuit shown in figure, if $${V_{CE}}\left( {sat} \right) = 0.1V,$$ the output logic low level $$\left( {{V_{OL}}} \right)$$ is

The transconductance $${g_m}$$ of the transistor shown in figure is $$10$$ $$mS.$$ The value of input resistance $${R_{in}}$$ is

For a tachometer if $$\theta \left( t \right)$$ is the rotor displacement is radians, $$e\left( t \right)$$ is the output voltage and $${K_t}$$ is the tachometer constant in V/rad/sec, then the transfer function $${{E\left( s \right)} \over {\theta \left( s \right)}},$$ will be