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LED Current Under Reverse Bias
Explain what happens to the current in the LED when the potential difference across the LED is negative.
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Marking points
- 1 States that the current is zero or stops.
- 2 Explains this using the LED’s very high reverse resistance or one-direction conduction.
Full-mark answer
The current is zero because an LED has a very high resistance in the reverse direction and allows current to pass in only one direction.
Why this answer loses marks
The current becomes negative.
The LED blocks current in this direction because of its very high reverse resistance and one-way conduction.