2023-05-20 01:33:56 +01:00
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$$E=hf$$
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## Photoelectric Effect
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- Emission of charged particles when exposed to UV light
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- Electrons
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- Einstein suggested light is quantised
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1. The maximum KE of ejected electrons is independent of intensity, but dependent on frequency $n$
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2. There is a minimum frequency n0below which there is no emission
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2023-05-21 14:49:15 +01:00
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3. No time delay (less than 1 ns) before the onset of emission –but the rate of electrons depends on the intensity.
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![[photo-electric.png]]
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![[fermi-vacuum-level.png]]
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![[em-spectrum.png]]
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- Radio spectrum
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- 30Hz – 300 GHz
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