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Science

What is The photoelectric effect?

The photoelectric effect is when light hitting a material knocks electrons loose from it. Einstein explained it by proposing that light comes in packets (photons) — work that helped launch quantum physics and underpins solar panels and digital cameras.

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Key things to understand

  • 1Light striking a material can eject electrons.
  • 2Einstein explained it using light 'packets' (photons).
  • 3It helped found quantum physics.
  • 4It powers solar cells and light sensors.

Frequently asked questions

What is the photoelectric effect?
The release of electrons from a material when light shines on it.
Why is the photoelectric effect important?
Einstein's explanation showed light behaves as particles (photons), a foundation of quantum physics.
Where is the photoelectric effect used?
In solar panels, light meters, image sensors, and many light-detecting devices.

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