A voltage commutated chopper operating at $$1$$ $$kHz$$ is used to control the speed of $$dc$$ motor as shown in figure. The load current is assumed to be constant at $$10$$ $$A.$$

The minimum time in $$\mu $$ sec for which the $$SCR$$ $$M$$ should be ON is

A single $$-$$ phase half wave uncontrolled converter circuit is shown in figure. A $$2$$ -winding transformer is used at the input for isolation. Assuming the load current to be constant and $${V_{in}} = {V_m}$$ $$\,\sin \omega t,$$ the current waveform through diode $${D_2}$$ will be

A voltage commutation circuit is shown in figure. If the turn off time of the $$SCR$$$$s$$ is $$50$$ $$\mu \sec $$ and as safety margin of $$2$$ is considered, what will be the approximate minimum value of capacitor required for proper commutation?

An $$SCR$$ having a turn ON time of $$5\,\,\mu \,\,\sec $$, latching current of $$50$$ $$mA$$ and holding current of $$40$$ $$mA$$ is triggered by a short duration pulse and is used in the circuit shown in figure The minimum pulse width required To turn the $$SCR$$ ON will be