Threshold frequency
What Threshold frequency means in Physics A-Level, as defined for AQA, OCR.
Definitions of Threshold frequency
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Reference: OCR
The minimum frequency of the radiation, depending on the metal, at or above which emission occurs; below it no emission occurs however intense the radiation is.
Visible light does not discharge the negatively charged electroscope because its frequency is below the threshold frequency for zinc.
The frequency above which electrons are emitted in the photoelectric effect, supporting a photon model of electromagnetic radiation.
The minimum frequency of incident electromagnetic radiation that can release electrons from the surface of a particular metal.
The frequency below which increasing intensity does not cause emission because no single photon has sufficient energy.
The frequency below which no electrons are emitted, however intense the light or however long it shines.
Topics that use Threshold frequency
- The discovery of photoelectricity (A-level only) (AQA A-Level)
- The photoelectric effect (AQA A-Level)
- Wave-particle duality (AQA A-Level)
- The photoelectric effect (OCR A-Level)
Related terms
- Intensity
- Maximum kinetic energy
- Photon
- Work function
- Conservation of energy in photon absorption
- de Broglie wavelength
- Development of scientific models
- Independence of KEmax from intensity
Using Threshold frequency in the exam
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