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Question
The anode of a thermionic diode is connected to the negative terminal of a battery and the cathode to its positive terminal.
Options
No appreciable current will pass through the diode.
A large current will pass through the diode from the anode to the cathode.
A large current will pass through the diode from the cathode to the anode.
The diode will be damaged.
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Solution
No appreciable current will pass through the diode.
If the anode is given a negative potential relative to the cathode, the electrons are pushed back to the cathode. Hence, no current will flow through the diode.
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