• # question_answer In a triode valve the plate current will be maximum when A)  both grid and plate are positive B)  both grid and plate are negative C)  grid is negative and plate is positive D)  grid is positive and plate is negative

In a triode valve the plate current according to Childs law is given by ${{i}_{P}}=K{{({{V}_{P}}+\mu {{V}_{g}})}^{3/2}}$ Clearly for maximum plate current, plate voltage (or anode voltage), ${{V}_{p}}$ and grid voltage ${{V}_{g}}$ both should be positive.