Light Waves Flashcards
Def of electromagnetic waves
Light, is a form of energy that does not need a medium to travel through
Radio waves
Satellite radio, traditional T.V., phones, wireless networks etc.
-used to change into sound
Microwaves
Wireless networks, cell phone towers, microwave ovens, weather radar, radio astronomy
-Electrical to light
Infrared
Heat lamps, thermography, night vision googles, short range communications
-Associated with heat (not visible)
Visible
Finger prints
-(low energy) red, orange, yellow, green, blue, violet (high energy)
-what we can see
Ultraviolet
Pest control, vitamin D, fluoresce, forensics, sterilization
X-rays
Medicine, x-ray astronomy
-Radiation
Gamma rays
Medicine, gamma ray astronomy, security
-Lasers
List the waves of light from LOWEST to HIGHEST
Radical
Martians
Invaded
Venus
Using
X ray
Guns
Non-Ionizing
Light giving off (visible)
-Radio
-Microwave
-IR
-Visibke
Can repair if harmed (safe)
Ionizing
Dangerous
-Can’t repair
-UV
-X rays
-Gamma rays
Newtons theory on light
Light is a Particle
-It can reflect and refract
—But waves can also reflect and refract
Young’s theory
Light is a wave
-It can interfere (constructive and destructive)
-Light diffracts(rainbow smeres)
-Particle CANNOT interfere
Fresnel
Light is a wave
-air can diffract
-Particles CANNOT diffract
Malus
Light is a wave
-can be polarized
Einstein
Light is a particle
-It can knock electrons out of atoms
-Photoelectric effect —> the more energy = ripping electrons away (ultra violet)
-Waves make electrons move
Mid 1900s theory
Light is a particle and a wave
-Particles CAN interfere
Interference
Multiple waves interacting with one another
EX = CDs and DVDs
Polarization
Blocks waves (transverse) that aren’t vibrant in up & down
EX = the black magic squares rotating them at a 90 degree angle
Refraction
the change in direction of a wave passing from one medium to another caused by its change in speed
Reflection
When the waves bounce off a surface or object and does not absorb the radiation
Diffraction
Bending around a barrier
A Wave can be…(5)
Reflection
Refraction
Interference
Diffraction
Polarization
NOT PHOTOELECTRIC EFFECT
A particle can be…(3)
Reflection
Refraction
Photoelectric
Doppler effect
Color changes because of its speed
-Blue/violet light = high frequency and shorter wavelength
-Red light =low low frequency and longer wavelength
Big Bang theory
how astronomers explain the way the universe began
Doppler effect for everyday life
Speed check, speed cameras, doppler radar (if clouds are rotating—> tornado)
What is the source of all electromagnetic waves?
Vibrating electrons
Young’s double split experiment
light is passed through two slits and forms an interference pattern on a screen behind the slits
Einsteins photoelectric effect
a phenomenon in which electrons are ejected from the surface of a metal when light is incident on it
-Light has particle like activity
When light is in a more dense medium it will… what will happen to the second medium?
It will bend AWAY from the normal line
Less to more…
Bends toward
More to less…
Does digress (away)
