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127 Cards in this Set
- Front
- Back
What is a rythmic disturbance that carries energy through matter or space?
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Wave
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What is a single disturbance traveling through a medium?
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Wave pulse
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What are the two main types of waves?
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Electromagnetic and mechanical
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What type of waves do not need a medium to travel through?
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Electromagnetic
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What type of waves require a source of energy and an elastic medium?
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Mechanical
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2 main kinds of mechanical waves
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Transverse and longitudinal
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type of mechanical waves causes particles to vibrate perpendicular to the direction of the wave
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Transverse
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type of mechanical waves causes particles to vibrate parallel to the direction of the wave
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Longitudinal
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position (displacement) and motion (velocity) of a point on a wave
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Phase
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Points on a wave are 180 degrees out of phase if...
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They have equal and opposite displacements and velocities
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linear distance between any point on the wave and the next closest point that's in phase with it
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Wavelength
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number of wavelengths/pulses that pass a given point each second
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Frequency
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time required for one wavelength/pulse to pass a given point
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Period
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SI unit of frequency
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Hertz
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linear distance traveled by the wave per unit of time
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speed
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EQUATION: V=
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(lambda) f
-------- OR ------- T (lambda) |
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max displacement of vibration particles from their equilibrium position
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Amplitude
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loss of energy (amplitude) due to friction
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damping
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Speed of Waves
1)doesn't depend on.. 2)doesn't depend on.. 3)depends on.. |
1)energy being transmitted
2)amplitude of wave 3)nature of wave and the medium |
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waves propogate in a straight line perpendicular to the wave front
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rectilinear propogation
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EQUATION: Law of reflection
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angle i = angle r
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bending of a wave around edge of a barrier
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diffraction
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points of zero displacement
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nodes
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points of max displacement
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loops
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sound waves are these types of mechanical waves
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longitudinal
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speed of sound in air at room temp.
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343 m/s
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amplitude of sound as measured on a log scale
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sound level
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sound level is measured in..
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decibels
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loudness of sound depends on 2 things..
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amplitude and frequency
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___ dB increase is perceived as a doubling of the loudness
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10
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most people can't hear below ___ Hz or above ___ Hz
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20-16,000
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people are most sensitive to sounds between ___ & ___ Hz
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1,000-5,000
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frequency of a sound wave
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pitch
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change in pitch due to relative motion between sound source and the ear
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dopplar shift
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created by constructive interference; high pressure wall that an object has to pass through to go faster than speed of sound
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sound barrier
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spy plane; flies 5 mi higher than other aircraft; fastest aircraft; almost invisible to radar
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blackbird
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fighter/bomber plane; often invisible to radar
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nighthawk/stealth fighter
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vibrating sound source is placed in contact with a larger object and forces it to vibrate
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forced vibrations
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a force is applied to an object everytime it undergoes a complete vibration
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resonance
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easiest frequency to produce in an object
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natural frequency
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a closed-pipe or open-pipe resonator resonates at ____ intervals
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1/2 lambda
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EQUATION:
L(b) - L(a) = |
1/2 lambda
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sound produced by an object vibrating only at its natural frequency
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pure tone
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tones which come from vibrations having a frequency greater than the fundamental frequency
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over tones
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depends on the number of overtones produced; richness
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quality/timbre
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refers to the number of overtones present plus their intensity
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harmonic content
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general string EQUATION:
k= |
f x l x d x '/D
--------------- '/F |
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interference effect from the superposition of 2 waves of slightly different frequency
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beat
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# of beats per sec =
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difference between frequency of component waves
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human ear can recognize up to ____ beats per sec
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10
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3 properties of light known during the 17th century
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1)regular reflection
2)refraction 3)rectilinear propogation |
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this theory said light consists of very small particles moving at a very fast speed; advocated by Newton
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Particle Theory
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this theory said light was a wave; advocated by Huygens
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Wave Theory
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advocated the wave theory
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Huygens
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advocated the particle theory
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Newton
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this man discovered light travels slower in water than air
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Foucault
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developed the electromagnetic theory
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James Clerk Maxwell
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confirmed the electromagnetic theory experiementally
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Hertz
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radiation just before red; gives sensation of warmth; causes atoms and molecules to move
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infrared radiation
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radiation just beyond violet; 3 different types
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ultraviolet radiation
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discovered x-rays
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Roentgen
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discovered radioactivity
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Becquerel
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discovered the electron
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Thomson
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3 radioactive elements.. 2 were discovered by the Curies
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thorium, polonium, radium
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3 types of radiation
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alpha, beta, gamma
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date of the birth of modern physics
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1900
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this hypothesis said vibrating particles in the hot objects studied only emit packets of energy
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Planck's Quantum Hypothesis
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packets of energy
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quanta/photons
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EQUATION: Planck's Quantum Hypothesis
E= |
h x f
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the emmission of electrons by a substance when illuminated by electromagnetic radiation
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photoelectric effect
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man who published the first quantitative studies of the photoelectric effect
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Lenard
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says light is made up of quanta/photons; explained the photoelectric effect
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Einstein's Quantum Theory of Light
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atomic spectra were first discovered by these 2 men
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Kirchoff and Bunsen
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order of the models of the atom
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Dalton's indestructable; Thomson's plum pudding; Rutherford's nuclear; Bohr's planetary
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discovered electric arc lamp
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Davy
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invented the first practical bulb
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Edison
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most efficient light
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Fluorescent
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science of how light interacts with life
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photobiology
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proposed that matter has wave properties
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de Broglie
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EQUATION:
wavelength of matter = |
h
--------- m x v |
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these two men confirmed de Broglie's prediction of the wavelength of matter
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Davison & Germer
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light with the same frequency
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monochromatic
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LASER =
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Light Amplification by Stimulated Emission Radiation
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first person to make a careful study of color
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Newton
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band of colors
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solar spectrum
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light consisting of many colors
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polychromatic
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2 properties of glass
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transparent & dispersive
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this spectrum is produced by incandescent solids, liquids, or gases under high pressure
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continuous
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this spectrum is produced by exciting a low density gas with heat or electricity
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bright-line
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this spectrum is produced by passing white light through a cool gas
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dark-line spectrum
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man who discovered the dark lines in the solar spectrum
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Fraunhofer
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if a star has a high frequency shift, it's moving
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toward us
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if a star has a low frequency shift, it's moving
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away from us
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complementary colors..
1)Red 2)Green 3)Blue |
1)Cyan
2)Magenta 3)Yellow |
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3 primary colors of light
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red, green, blue
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3 primary pigments
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magenta, yellow, cyan
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you can see a rainbow when..
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1)the sun is behind you
2)angle formed is 40-42 |
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light that only vibrates in one plane
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polarized light
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emission of light during the absorption of radiation
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fluorescence
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emission of light after the light sorce has been removed
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phosphorescence
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EQUATION: law of refration (snell's law)
n = |
sin i V(air)
n = ----- = ----- sin r V(material) |
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branch of electronics that deals with static electricity
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electrostatics
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matter through which an electron can easily pass
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conductor
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matter through which electons can't easily pass through
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insulator
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EQUATION:
F = |
Q1 x Q2
K x ------- d^2 |
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described by lines of flux
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magnetic field
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described by lines of force
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electric field
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EQUATION: Electric Field Intensity
E= |
F/q
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rate of flow of charge through a conductor
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electric current
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SI unit of electric current
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ampere (A)
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opposition electrons encounter as they pass through conductor
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electric resistance
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SI unit of resistance
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ohm
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conducting loop of wire through which a current can transfer electric energy from a suitable source to a useful load
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electric circuit
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safety current must go through
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fuse
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magnetic switched which open when circuit is overloaded
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circuit breakers
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tells you how much energy electrons have coming from a power source
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voltage
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EQUATION: Ohm's Law
V = |
I x R
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rate at which electrical energy is used
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electrical power
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EQUATION:
P = |
I x V
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more devoid of matter than the best vacuum on earth
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interstellar space
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a nebula turns into a
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globule
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a globule turns into either a
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planet or star
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a red giant turns into a
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white dwarf
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a white dwarf turns into one of 3 things..
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black dwarf, nova, supernova type I
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emits pulses of electromagnetic radiation; neutron star
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pulsar
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first person to do calculations that explained a black hole
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Oppenheimer
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consumes stars and releases tremendous amounts of energy when its first formed
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quasar
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