The grid in a triode valve is used

The amplification factor of a triode is $20$. If the grid potential is reduced by $0.2\, V$,then to keep the plate current constant,its plate voltage must be increased by how many volts?

$A$ triode has a plate resistance of $10 \, k\Omega$ and an amplification factor of $24$. If the input signal voltage is $0.4 \, V$ $(r.m.s.)$ and the load resistance is $10 \, k\Omega$,then the output voltage $(r.m.s.)$ is ...... $V$.

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 ${V_g} = -2 \text{ V}$?

The introduction of a grid in a triode valve affects plate current by

Write the differences between vacuum tube (valve) electronic devices and semiconductor electronic devices.