Diodes are described as valves for current.

Diodes are described as valves for current.

• A. True
• B. False
• C. Only in reverse bias
• D. Only at high temperatures

Answer: (A)

Diodes act as one-way valves for electric current. When the anode is more positive than the cathode (forward bias), the depletion region at the p–n junction narrows and charge carriers can cross, so current flows—like opening a valve to let fluid through. In reverse bias, the depletion region widens and only a tiny leakage current passes, effectively blocking the main current—like closing the valve. So describing a diode as a valve for current captures this directional control, making the statement true. The other options aren’t correct because normal diode operation relies on forward bias for conduction, not high temperature, and it does not conduct in reverse bias (except for unlikely breakdown scenarios).

Diodes act as one-way valves for electric current. When the anode is more positive than the cathode (forward bias), the depletion region at the p–n junction narrows and charge carriers can cross, so current flows—like opening a valve to let fluid through. In reverse bias, the depletion region widens and only a tiny leakage current passes, effectively blocking the main current—like closing the valve. So describing a diode as a valve for current captures this directional control, making the statement true. The other options aren’t correct because normal diode operation relies on forward bias for conduction, not high temperature, and it does not conduct in reverse bias (except for unlikely breakdown scenarios).