Light Flashcards
What is electromagnetic radiation ?
The behavior of light
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What does the UV spectrum look like ? (parameters)
Goes from gamma rays –> radio waves
- cool –> warm colors
- frequency and energy increases as it goes left
- size and wavelength decreases as it goes left
What are the 5 parameters of light as a wave ?
wavelength (distance b/w peaks), frequency (# of wavelengths), amplitude (height of peaks), energy, and velocity
How to determine frequency ?
velocity divided by frequency
What to do with exponents when dividing stuff ?
subtract them
What is diffraction ?
when light bends as it passes through a barrier w/ a slit
What are the 2 types of interference and explain e/a
- constructive (waves go together): reinforce
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\ / \ / - destructive (go opposite): cancel out
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*think of two people jumping on a trampoline (Jump together = jump higher, land timing weird=cancels jump)
What experiment supported light as a wave ? Explain process
Double slit experiment
- beam of particles directed at barrier w/ 2 slits
- light and dark bands on wall
- light = constructive
- dark = destructive
*think sun shining through blinds
How can light be a particle ?
- When light shines on metal surface, it emits electrons
- light transfer energy to electrons –> turns into kinetic energy that give electrons energy to leave surface
What binds the particles to the metal
electromagnetic forces
What are light particles called ?
photons
What happens if there’s not enough energy ?
No electrons are ejected
What does the # of electrons depend on ?
frequency and sometimes intensity
