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?

In a triode,${g_m} = 2 \times 10^{-3} \, \Omega^{-1}$,$\mu = 42$,and the resistance load $R_L = 50 \, \text{k}\Omega$. The voltage amplification obtained from this triode will be:

For a triode,at ${V_g} = -1 \text{ V}$,the following observations were taken: ${V_p} = 75 \text{ V}, {I_p} = 2 \text{ mA}$ and ${V_p} = 100 \text{ V}, {I_p} = 4 \text{ mA}$. The value of plate resistance will be ...... $k\Omega$.

Why is a vacuum tube called a valve in electronics?

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

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