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In support of all the students who are displaced from school due to the Corona virus. Access to physics zone and chemistry zone lessons are now available free of charge. This will be maintained at least through August 1st 2020. Learn and be well.

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The Photoelectric Effect

The photoelectric effectAn effect had been noticed early on that when light of a high enough frequency is shined on a metal, the metal will eject electrons.  This one effect and all of its subtle clues led Albert Einstein in 1905 to propose that light behaves as a particle-like wave packet called a photon.  The majority of prominent physicists strongly opposed this notion for a period of about 10 years.  It wasn't until 1915 when Robert Millikan (initially trying to disprove Einstein's theory) ended up verifying it completely, and convinced the rest of the physics world.

As you go through this lesson, you will be presented with what should happen if light is a wave, and what should happen if it is a particle.  Then you will be shown which is real based on experimental observations.

  1. Photoelectric Effect Apparatus
  2. Frequency of Incoming Light
  3. Threshold Frequency & Work Function
  4. Intensity of Incoming Light
  5. Different Materials