Contents
Key Stage 4
Meaning
A light emitting diode (LED) is an electrical component which emits light when electricity passes through in one direction and prevents electricity from going in the reverse direction.
About Light Emitting Diodes
- LEDs have a low resistance in one direction and emit light but a very high resistance in the reverse direction and do not emit light.
- LEDs can be used to change an alternating current into a direct current.
IV Graph
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Description
The IV Graph for an LED shows that:
- For a positive potential difference the current increases rapidly with an increase in potential difference
- For a negative potential difference the current remains negligible and does not increase as the potential difference becomes larger.
Explanation
- The resistance of an LED is very low for current in the forward direction and very high in the back direction.