2011 년 11 월 25 일 제 10 장

 The Quantum Hypothesis  The Photoelectric Effect and Photons  Atomic Spectra  The Bohr Model of the Atom  Quantum Mechanics  Atomic Structure  X-Ray Spectra  Lasers

 Fluorescent light  Plasma TV

 End of 19 th century ◦ Newtonian mechanics ◦ Electromagnetism by Maxwell ◦ Everything is resolved  New experiments ◦ Blackbody radiation ◦ Photoelectric effect ◦ Atomic spectra

 Absorb all radiation and perfect emitter, as temperature increase ◦ More energy at each wavelength ◦ Smaller Peak energy wavelength

 Discovered by Heinrich Hertz

 Energies of each color

 Light detector  Photocopy  Laser printer

 Photocopying process

 Light bulb creates continuous spectrum

 Structure Atom is not believed  Rutherford’s experiment

 Atom forms a miniature of solar system  Electron orbits are quantized  Electrons may jump from one orbit to another

 1925 Davisson and Germer experiment

 Radius of hydrogen atom

 Energy levels  Quantum numbers

 n=3 -> n=2

 Two electrons cannot occupy precisely the same quantum state at the same time ElementAtomic Number n=1n=2n=3 Hydrogen1100 Helium2200 Lithium3210 Carbon6240 Oxygen8260 Neon10280 Sodium11281

 Light Amplification by Stimulated Emission of Radiation