ASTRON 2B03 Lecture Notes - Lecture 13: Blueshift, Quantum Tunnelling, Photon
12 Oct 2018
School
Department
Course
Professor
Document Summary
What is light: light behaves as a wave. Frequency f (same as pitch in sound; how many times it repeats every second) Wavelength l (distance between tops or bottoms of wave) So what do you see if you run towards a beam of light: speed of light doesn(cid:495)t change but you will encounter more wave crests (blueshift) Quantum weirdness: our everyday experience did not prepare us for what happens at high speed (relativity) Born; dirac; others: discovered over 20 yrs by planck; einstein; bohr; schroedinger; heisenberg; In 1900 max planck set out to explain a problem with something called black body radiation: this was not what was expected from wave theory. Momentum: normal (cid:523)classical(cid:524) physics, )f you want to knock something around, you need momentum, momentum = mass x speed p = m v. Planck(cid:495)s photoelectric effect discovery metal: when light is shone on a piece of metal, electrons are knocked out of the, not the result of waves.
