Question
Explain Hertz's observations for the photoelectric effect.
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Explain how the photoelectric effect was discovered by Hertz.
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Explain how the photoelectric effect was discovered by Hertz.
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Answer
→In an experiment to produce electromagnetic waves in a laboratory, when negatively charged particles (electrons) are emitted from a metal plate and passed through a spark gap, a spark is generated in front of a detector loop and electromagnetic waves are emitted.
→Hertz observed that when rays of ultraviolet light were irradiated on a metal surface with an arc lamp, the spark before the detector loop increased. That is the number of electrons passing through the spark gap also increases.
→When ultraviolet light is incident on a metal plate the free electrons in the metal must absorb the energy of the radiation and since this energy is sufficient the electrons must escape from the attraction of the positive ions of the metal, which is the photoelectric effect.
→Thus, Hertz first observed the photoelectric effect in 1887 during his experiments on the emission of electromagnetic waves.
→Hertz observed that when rays of ultraviolet light were irradiated on a metal surface with an arc lamp, the spark before the detector loop increased. That is the number of electrons passing through the spark gap also increases.
→When ultraviolet light is incident on a metal plate the free electrons in the metal must absorb the energy of the radiation and since this energy is sufficient the electrons must escape from the attraction of the positive ions of the metal, which is the photoelectric effect.
→Thus, Hertz first observed the photoelectric effect in 1887 during his experiments on the emission of electromagnetic waves.
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