The maximum efficiency of a full-wave rectifier is .........$\%$

In the half-wave rectifier circuit shown,which of the following waveforms is true for $V_{CD}$,the output across $C$ and $D$?

If a full wave rectifier circuit is operating from $50 \,Hz$ mains, the fundamental frequency in the ripple will be (in $\,Hz$)

In a full-wave rectifier circuit without a filter,the output current is

In a half-wave rectifier using a $PN$ junction diode, the input voltage has an amplitude of $25 \ V$ and a frequency of $50 \ Hz$. No filter is used, and the load resistance is $1000 \ \Omega$. The forward resistance of the diode is $10 \ \Omega$. The efficiency of the rectifier is approximately ...... $\%$.

For a half-wave rectifier, the load resistance is $R_L = 2 \, k\Omega$ and the $P-N$ junction diode resistance is $R_d = 2 \, k\Omega$. The rectification efficiency is .... $\%$.