Constant $DC$ voltage is required from a variable $AC$ voltage. Which of the following is the correct order of operation?

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 ripple factor is:

An alternating voltage of $141.4\,V$ (rms) is applied to a vacuum diode as shown in the figure. The maximum potential difference across the condenser will be......$V$

For the given circuit,the output voltage across the load resistance $R_L$ will be:

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

In the diagram,the input is across the terminals $A$ and $C$ and the output is across the terminals $B$ and $D$,then the output is