MCQ
The photoelectric effect proves that light consists of :
- APhotons
- BElectrons
- CElectromagnetic waves
- DMechanical waves
✓
Answer
- Photons
Explanation:
It's been determined experimentally that when light shines on a metal surface, the surface emits electrons. For example, you can start a current in a circuit just by shining a light on a metal plate. we were saying earlier that light is made up of electromagnetic waves, and that the waves carry energy. So if a wave of light hit an electron in one of the atoms in the metal, it might transfer enough energy to knock the electron out of its atom. Light has sometimes been viewed as a particle (photon) rather than a wave. If it's waves, the energy contained in one of those waves should depend only on its amplitude--that is, on the intensity of the light.
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