For a given plate-voltage,the plate current in a triode is maximum when the potential of

If ${R_p} = 7 \text{ k}\Omega$ and ${g_m} = 2.5 \text{ millimho}$, then on increasing the plate voltage by $50 \text{ V}$, how much must the grid voltage be changed so that the plate current remains the same? (in $V$)

The plate current in a triode is given by ${I_p} = 0.004 ({V_p} + 10{V_g})^{3/2} \text{ mA}$,where ${I_p}, {V_p}$ and ${V_g}$ are the values of plate current,plate voltage,and grid voltage,respectively. What are the triode parameters $\mu$,${r_p}$ and ${g_m}$ for the operating point at ${V_p} = 120 \text{ V}$ and ${V_g} = -2 \text{ V}$?

For a triode,$\mu = 64$ and $g_m = 1600 \, \mu \text{mho}$. It is used as an amplifier and an input signal of $1 \, V \text{ (rms)}$ is applied. The signal power in the load of $40 \, k\Omega$ will be......$mW$.

In a triode valve,the amplification factor is $20$ and the mutual conductance is $10^{-3} \text{ mho}$. The plate resistance is:

How many electrodes are in the tetrode?