Question | Answer |
1600's - Huygens | Wave Theory - waves in ether |
1600's - Newton | Corpuscular Theory - light travels as a stream of particles |
1670 - Ola of Romer | Danish astronomer that timed the eclipse of Jupiter's moons |
1800's - Maxwell | Electromagnetic Theory of Light - improved with math |
1800's - Hertz | produced electromagnetic waves in a lab proving Maxwell |
1849 - Fizeau | used a toothed cogwheel and a mirror to measure speed of light; 187,000 mi/sec |
1900 - Plank | Photon Theory (Quantum Theory) - divided light into small portions called quanta. |
1905 - Einstein | used quantum theory to explain the photo-electric effect |
1923 - Michaelson | used an octagonal moving mirror experiment to show light travels 186,285 mi/sec in air and 186, 720 mi/sec in a vacuum |
Source | generates light |
Point source | infinitely small source of light |
Extended source | more than one point of light |
monochromatic source | A source that produces just one wavelength (color) |
polychromatic source | A source that produces multiple wavelengths (colors) |
geometric optics | Light traveling in straight lines |
physical optics | light traveling in waves, also describes "diffraction" |
Diffraction | light bending around corners |
wavelengths for visible light | 380-760 nm (400-800) |
wavelengths used to calculate index of refractions | 587.56 nm (yellow) |
What are the three factors that influence shift? | Index of Refraction; Angle of Incidence; Thickness of the Medium |
When any of the influences are increased, the shift will become ________? | Greater |
What is critical angle? | The angle of incidence when angle r = 90 degrees. |
When can you exceed the critical angle? | When going from a higher index of refraction into a lower index of refraction medium. |
If angle i is less than the critical angle the ray is....? | Refracted into the second medium |
If angle i is more than the critical angle the ray is...? | Reflected back into the first medium....known as total internal reflection |
How do you find the critical angle? | Use Snell's Law and let angle r = 90 degrees |
Memorize formulas for Lateral Shift, Apparent Depth when viewing along the normal, and Apparent Depth when viewing from an angle! | |