The mutual characteristic of a triode is represented by which of the following graphs?

In the grid circuit of a triode,a signal $E = 2\sqrt{2} \cos(\omega t)$ is applied. If the amplification factor $\mu = 14$ and the plate resistance $r_p = 10\,k\Omega$,then the root mean square $(RMS)$ current flowing through the load resistance $R_L = 12\,k\Omega$ will be.......$mA$.

The current in a triode at anode potential $100 \, V$ and grid potential $-1.2 \, V$ is $7.5 \, mA$. If the grid potential is changed to $-2.2 \, V$, the current becomes $5.5 \, mA$. The value of transconductance $(g_m)$ will be .... $mili \, mho$.

Before the saturation state of a diode,at plate voltages of $400 \, V$ and $200 \, V$,the currents are $i_1$ and $i_2$ respectively. The ratio $i_1/i_2$ will be:

The amplification factor of a triode is $20$,the trans-conductance is $3 \text{ mS}$ (milli mho),and the load resistance is $3 \times 10^4 \ \Omega$. Calculate the voltage gain.

In an electron gun,the control grid is given a negative potential relative to the cathode in order to: