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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.
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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