The correct relation for a triode is:

In a triode valve,which of the following statements is correct?

For a triode, ${r_p} = 10 \text{ k}\Omega$ and ${g_m} = 3 \text{ m}\mho$. If the load resistance is double the plate resistance, then the value of the voltage gain will be:

In a diode valve,the cathode temperature must be ($\phi$ = work function):

The plate resistance of two triode valves is $2 \, k\Omega$ and $4 \, k\Omega$. The amplification factor of each valve is $40$. The ratio of voltage amplification,when used with a $4 \, k\Omega$ load resistance,will be:

The grid voltage of any triode valve is changed from $-1 \, V$ to $-3 \, V$ and the mutual conductance is $3 \times 10^{-4} \, \text{mho}$. The change in plate circuit current will be ..... $mA$.