In a triode valve

1) If the grid voltage is zero then plate current will be zero

2) If the temperature of the filament is doubled, then the thermionic current will also be doubled.

3) If the temperature of the filament is doubled, then the thermionic current will nearly be four times

4) At a definite grid voltage, the plate current varies with plate voltage according to Ohm’s law

3) If the temperature of the filament is doubled, then the thermionic current will nearly be four times