Atoms

							Atoms


  Chapters 8
Light
   Oscillating electric
    field
   Matching oscillating
    magnetic field
   Frequency range
    varies widely
   Speed of waves are
    constant
Interaction of Light with Matter
   Microwave oven (water rotation)
   IR heat lamps (warm food)
   Radio waves (communication)
   Visible (sight)
   X-rays (medical)
Simple Light Calculations
   FM Radio = 95 MHz = 95x106 Hz
       Wavelength = 3.16 m
   AM Radio = 1410 KHz = 1410x103 Hz
       Wavelength = 213 m
   Visible Light = 8x1014 Hz
       Wavelength = 3.75x10–9 m = 375 nm
Matter is made of Atoms
   Small objects
       10-10 m diameter
       1025 in your body
       Building blocks
       Different types
History
   Greeks (Earth, Air, Fire, Water)
   Alchemists
       About 25 common types of elements
       Change lead into gold
   Dalton
Changes to Atomic Models
   Thomson, Rutherford, Bohr
       Charges, nucleus, orbits
Can we see them?
   Brownian motion
   Atomic force microscopy
Bohr Atom
   Electrons orbiting nucleus
   Specific distances (wave quantization)
Light and Atoms
   Absorption and Emission