Michelson-Morley Experiment
In the Michelson-Morley experiment, these two scientists attempted to find the "luminiferous aether," or medium of light.  They wanted to find out whether or not the medium existed to see if light travelled at different speeds in the earth's reference frame in space.  They thought that if there was an aether wind, it would slow down the speed of light.  The two light paths would be travelled with slightly different speeds because one would be perpendicular to the aether wind while the other will be parrallel.  Therefore it would have destructive interference at some point, but it never did.  Instead it was always constructive meaning that the two light's speed were the same.  They rotated it around its base to try every angle.  They never found any destructive interference.  They thought they did it wrong,but many scientist have since tried the experiment and have never been successful in finding an Aether wind.
 

Rutherford Gold Foil Experiment:
Rutherford conducted this experiment to prove that Thompson's theory of negative charges sitting in a positive plasma in an atom incorrect. To set up the experiment, he had his radioactive source encased in lead with a hole to project the radiated alpha particles at a thin sheet of gold foil. He put a screen around the foil to see where the deflected alpha particles were directed. Once the experiment was run, he noticed that a very large majority of the alpha particles went straight through, undeflected. There were others that strayed to left or right, and few that went out to either side. What Rutherford wasn't expecting, however, is that there were a few that came straight back! What he concluded form this was that the atom was made of mostly empty space, with a very dense, very small positive nucleus at the center. The alpha particles that came straight back must have hit the nucleus right in the center.
 

Compton Scattering Effect:

    The Compton Scattering Effect was done to provide more justification to the photon theory of light.  It used x-rays of a certain wavelength, and emitted them onto a graphite block.  After the x-rays passed through the block some scattered at different angles, and were found to have different wavelengths, which meant that the photons, collided with one of the electrons within the sea of electrons in graphite and deflected the photon, taking some of the energy away from it during the collision.  Using E=hf, if the energy goes down, then the frequency must go down since h is a constant.  Also determined from this experiment was that the energy change and thus the frequency change depended on the angle that the photons deflected.
     Pair Production and Annihilation:
    Pair production is when a photon and a Mass collide and the photon disappears and in its place is a Positron and an Electron.  Pair annihilation is when a Positron and an Electron collide and produce Photons.  Momentum is always conserved in these collisions.
 

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Note: These experiments are not Earl's work, but the famous experiments of noted scientists of the 20th century.