In the following circuit,the reading of the ammeter will be (Take Zener breakdown voltage $= 4 \ V$) (in $mA$)

Why is there a sudden increase in current in a Zener diode?

For the circuit shown below,the current through the Zener diode is......$mA$

The $I-V$ characteristics of an electronic device are shown in the figure. The device is $:-$

$A$ Zener diode of breakdown voltage $V_{Z} = 8\,V$ and maximum Zener current $I_{ZM} = 10\,mA$ is subjected to an input voltage $V_{i} = 10\,V$ with a series resistance $R = 100\,\Omega$. In the given circuit,$R_{L}$ represents the variable load resistance. The ratio of the maximum and minimum value of $R_{L}$ is

$A$ Zener diode in the circuit shown has a knee current of $5\,mA$ and a maximum allowed power dissipation of $300\,mW$. What are the minimum and maximum load currents that can be drawn safely from the circuit, keeping the output voltage $V_0$ constant at $6\,V$?