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

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

$A$ Zener diode having breakdown voltage $V_z = 6 \, V$ is used in a voltage regulator circuit as shown in the figure. The minimum current required to pass through the Zener to act as a voltage regulator is $10 \, mA$ and the maximum allowed current through the Zener is $40 \, mA$. The maximum value of $R_s$ for the Zener to act as a voltage regulator is (in $\Omega$)

$A$ Zener diode with a power rating of $1 \, W$ is to be used as a voltage regulator. If the Zener diode has a breakdown voltage of $5 \, V$ and it has to regulate an input voltage that fluctuates between $3 \, V$ and $7 \, V$,what should be the value of the series resistance $R_s$ for safe operation? (See figure)

The Zener diode is used for

Two Zener diodes ($A$ and $B$) having breakdown voltages of $6\, V$ and $4\, V$ respectively,are connected as shown in the circuit below. The output voltage $V_{0}$ variation with input voltage linearly increasing with time,is given by: $(V_{\text{input}} = 0\, V$ at $t = 0)$ (figures are qualitative).