A diode turns on when forward bias is applied, making which terminal more positive?

A diode turns on when forward bias is applied, making which terminal more positive?

• A. Reverse-biased diode
• B. Forward-biased diode
• C. Open circuit
• D. Short circuit

Answer: (B)

Forward bias is the condition that makes a diode conduct. When a diode is forward biased, the anode is driven more positive than the cathode, which reduces the barrier at the p-n junction and allows current to flow from anode to cathode. Since the question asks which terminal becomes more positive under this condition, the relevant description is the forward-biased state itself—the diode is in a conducting, forward-biased mode. The other described states don’t match this behavior: reverse bias keeps the anode at a lower potential than the cathode and the diode stays off; an open circuit or a short circuit describes circuit outcomes rather than the polarity of the diode’s terminals in forward conduction.

Forward bias is the condition that makes a diode conduct. When a diode is forward biased, the anode is driven more positive than the cathode, which reduces the barrier at the p-n junction and allows current to flow from anode to cathode. Since the question asks which terminal becomes more positive under this condition, the relevant description is the forward-biased state itself—the diode is in a conducting, forward-biased mode. The other described states don’t match this behavior: reverse bias keeps the anode at a lower potential than the cathode and the diode stays off; an open circuit or a short circuit describes circuit outcomes rather than the polarity of the diode’s terminals in forward conduction.