Threshold voltage
What Threshold voltage means in Physics A-Level, as defined for AQA, OCR.
Definitions of Threshold voltage
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Reference: AQA
The gate-source voltage above which electrons are attracted to the surface, forming an induced n-channel that connects source and drain.
The gate-source voltage above which electrons are attracted to the surface and an n-type inversion channel forms.
The voltage at which the LED just begins to emit light, corresponding to the minimum photon energy.
Topics that use Threshold voltage
- MOSFET (metal-oxide semiconducting field-effect transistor) (A-level only) (AQA A-Level)
- Photons (OCR A-Level)
Related terms
- Electronvolt
- Enhancement MOSFET
- Experimental uncertainty and evaluation
- Gate
- Induced n-channel
- Insulating oxide layer
- Linearising data using 1/λ
- n-type inversion channel
Using Threshold voltage in the exam
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