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					Motion
Aristotle
   4 elements that are the building blocks of the
    world around us: _______________,
    _______________, _______________,
    _______________
       Rock – belongs to the earth element, would fall
        back to the earth
       Smoke – belongs to the fire element, rises above
        air
Aristotle
   _______________ Motion – straight up
    and straight down motion
       Circular motion is the natural motion of the
        heavens – all the planets revolve around the earth

   _______________ Motion – result of
    forces that pushed or pulled – from some
    external cause
       Cart being pulled by a horse
Copernicus
   Studied the planets
   Earth and the other planets move around the
    sun.
   Worked on this idea in secret to escape
    persecution.
   The day he died, he received his work in print
    (1543)
Galileo
   Expanded on Copernicus’ ideas
   Brought in the concept of ______________
       Time for the motion to happen
   A study of motion will involve the introduction
    of a variety of quantities which are used to
    describe the physical world.
   Examples of such quantities include distance,
    displacement, speed, velocity, acceleration,
    force, mass, momentum, energy, work,
    power, etc.
   All these quantities can by divided into two
    categories:
     _______________
           A vector quantity is a quantity which is fully described
            by both magnitude and direction.
       _______________
           A scalar quantity is a quantity which is fully described
            by its magnitude.
Vector Quantities
 _______________
 _______________

 _______________

 _______________
Linear Motion
   Motion in a straight line
   _______________ – measure of how fast
    something is moving
       mph
   _______________ – speed in a given
    direction
       m/s northward
   _______________ – the rate at which
    velocity is changing
       m/s2
       Can be positive or negative
Projectile Motion
   The most common example of an object
    which is moving in two-dimensions is a
    _______________.

   A projectile is an object upon which the only
    force acting is _______________.
   A projectile is any object which once
    projected _______________ in motion by
    its own inertia and is influenced only by the
    downward force of gravity.
       an object dropped from rest is a projectile
        (provided that the influence of air resistance is
        negligible)
       an object which is thrown vertically upwards is
        also a projectile (provided that the influence of air
        resistance is negligible)
       an object is which thrown upwards at an angle is
        also a projectile (provided that the influence of air
        resistance is negligible).
Horizontally Launched
Projectiles

   Imagine a cannonball being launched from a
    cannon atop of a very high cliff. Imagine as
    well that the cannonball does not encounter a
    significant amount of air resistance. What will
    be the path of the cannonball and how can
    the motion of the cannonball be described?
   The animation below depicts such a
    situation. The path of the cannonball is
    shown; additionally, the horizontal and
    vertical velocity components are
    represented by arrows in the animation.
   As the cannonball falls, it undergoes a
    downward acceleration. A downwardly-
    moving cannonball which is gaining speed
    is said to have a downward acceleration.
   This downward acceleration is attributed to
    the downward force of gravity which acts
    upon the ball.
Acceleration Due to Gravity
   Galileo – objects fall at the same rate
       Did recognize that a compact object does fall
        faster than a less compact object (flat paper vs.
        crumpled paper)
       Acceleration due to gravity (g) = 9.8 m/s2
       Objects fall with the same _______________
        but it will be dependent on _______________
           1971, David Scott, US Astronaut, dropped a hammer
            and a feather on the moon and they hit the surface of
            the moon at the same time
Newton’s First Law of Motion
   an object in motion continues in motion with
    the same speed and in the same direction
    unless acted upon by an unbalanced force.
   It is the natural tendency of objects to keep
    on doing what they're doing.
   All objects _______________ in their state
    of motion.
   In the absence of an unbalanced force, an
    object in motion will maintain this state of
    motion. This is often called the
    _______________.
   Inertia is the _______________ an
    object has to a change in its state of
    motion. Inertia is dependent only on
    _______________.
   At the time, Newton's concept of inertia was in
    direct opposition to the more popular
    conceptions about motion.
   The dominant thought prior to Newton's day was
    that it was the natural tendency of objects to
    come to rest.
   Moving objects, or so it was believed, would
    eventually stop moving since a force was
    necessary to keep an object moving.
   If left to itself, a moving object would eventually
    come to rest and an object at rest would stay at
    rest; thus, the idea which dominated the thinking
    for nearly 2000 years prior to Newton was that it
    was the natural tendency of all objects to
    assume a rest position.
   Newton's first law of motion declares that a
    _______________ is not needed to keep an
    object in motion.
   Slide a book across a table and watch it slide to a
    stop.
   The book in motion on the table top does not come
    to rest because of the absence of a force; rather it is
    the presence of a force – the force of
    _______________ – which brings the book to a
    halt.
   The law of inertia is most commonly
    experienced when riding in cars and trucks.
   In fact, the tendency of moving objects to
    continue in motion is a common cause of a
    variety of transportation accidents - of both
    small and large magnitudes.
   Consider for instance the unfortunate
    collision of a car with a wall.
   Upon contact with the wall, an unbalanced
    force acts upon the car to abruptly
    decelerate it to rest.
   Any passengers in the car will also be
    decelerated to rest if they are strapped to
    the car by seat belts. Being strapped
    tightly to the car, the passengers share
    the same state of motion as the car.
   As the car accelerates, the passengers
    accelerate with it; as the car decelerates, the
    passengers decelerate with it; and as the car
    maintains a constant speed, the passengers
    maintain a constant speed as well.
   But what would happen if the passengers
    were not wearing the seat belt? What motion
    would the passengers undergo if they failed
    to use their seat belts and the car were
    brought to a sudden and abrupt halt by a
    collision with a wall?
   Were this scenario to occur, the passengers
    would no longer share the same state of motion
    as the car. The presence of the strap assures
    that the forces necessary for accelerated and
    decelerated motion exist. Yet, once the strap is
    no longer present to do its job, the passengers
    are more likely to maintain its state of motion.
   If the car were to abruptly stop and the seat
    belts were not being worn, then the
    passengers in motion would continue in
    motion. Assuming a negligible amount of
    friction between the passengers and the seats,
    the passengers would likely be propelled from
    the car and be hurled into the air. Once they
    leave the car, the passengers becomes
    projectiles and continue in projectile-like
    motion.
   But why then are motorcycles not
    equipped with safety harnesses? Is this
    a gross oversight made by motorcycle
    manufacturers?
There are many more applications
of Newton's first law of motion.
   blood rushes from your head to your feet when riding on a
    descending elevator which suddenly stops.
   the head of a hammer can be tightened onto the wooden handle
    by banging the bottom of the handle against a hard surface.
   a brick is painlessly broken over the hand of a physics teacher by
    slamming the brick with a hammer. (CAUTION: Do not attempt
    this at home!)
   to dislodge ketchup from the bottom of a ketchup bottle, the
    bottle is often turned upside down, thrust downward at a high
    speed and then abruptly halted.
   headrests are placed in cars to prevent whiplash injuries during
    rear-end collisions.
   while riding a skateboard (or wagon or bicycle), you fly forward
    off the board when hitting a curb, a rock or another object which
    abruptly halts the motion of the skateboard.
   1. Imagine a place in the cosmos far from all
    gravitational and frictional influences. Suppose an
    astronaut in that place throws a rock. The rock will:



   2. Mac and Tosh are arguing in the cafeteria. Mac
    says that if he throws his jello with a greater speed
    it will have a greater inertia. Tosh argues that
    inertia does not depend upon speed, but rather
    upon mass. With whom do you agree? Why?
   3. If you were in a weightless environment in
    space, would it require a force to set an object in
    motion?




   4. Mr. Wegley spends most Sunday afternoons at
    rest on the sofa, watching pro football games and
    consuming large quantities of food. What effect
    (if any) does this practice have upon his inertia?
    Explain.
   Ben Tooclose is being chased through the
    woods by a bull moose which he was
    attempting to photograph. The enormous
    mass of the bull moose is extremely
    intimidating. Yet, if Ben makes a zigzag
    pattern through the woods, he will be able to
    use the large mass of the moose to his own
    advantage. Explain this in terms of inertia and
    Newton's first law of motion.
Newton’s Second Law of
Motion
   Objects at _______________ (the condition in
    which all forces balance) will not accelerate.

   According to Newton, an object will only accelerate if
    there is a net or unbalanced force acting upon it.

   Newton's second law of motion pertains to the
    behavior of objects for which all existing forces are
    not balanced.
   The second law states that the acceleration
    of an object is dependent upon two variables
    – the net force acting upon the object and the
    mass of the object.

   As the net force increases, so will the object's
    acceleration. However, as the mass of the
    object increases, its acceleration will
    decrease.
         Fnet = ma
1 Newton = amount of force needed to move a
             1 kg object 1 m/s2
Misconception of Motion
   The idea that sustaining motion requires a
    continued force.
Newton’s Third Law of Motion
   "For every action, there is an equal and
    opposite reaction."
   The statement means that in every
    interaction, there is a pair of forces acting on
    the two interacting objects.
   The size of the force on the first object equals
    the size of the force on the second object.
   The direction of the force on the first object is
    opposite to the direction of the force on the
    second object. _______________ always
    come in pairs – equal and opposite action-
    reaction force pairs.
   While driving, Anna Litical observed a bug
    striking the windshield of her car. Obviously,
    a case of Newton's third law of motion. The
    bug hit the windshield and the windshield hit
    the bug. Which of the two forces is greater:
    the force on the bug or the force on the
    windshield?
   2. Rockets are unable to accelerate in space
    because ...
    a. there is no air in space for the rockets to
        push off of.
    b. there is no gravity is in space.
    c. there is no air resistance in space.
    d. ... nonsense! Rockets do accelerate in
        space.
Momentum
   _______________ in motion

   Mass x Velocity


   The greater the _______________ acting on an
    object, the greater the change in the velocity, and
    the greater the change in momentum.


   The more _______________ which an object
    has, the harder that it is to stop.
   From the definition of momentum, it becomes
    obvious that an object has a large momentum if
    either its mass or its velocity is large.
       Consider a Mack truck and a roller skate moving down the
        street at the same speed. The considerably greater mass
        of the Mack truck gives it a considerably greater
        momentum.
       Yet if the Mack truck were at rest, then the momentum of
        the least massive roller skate would be the greatest; for the
        momentum of any object which is at rest is 0.
       Objects at rest do not have momentum - they do not have
        any "mass in motion."
Collisions
   The physics of _______________ are
    governed by the laws of momentum and
    Newton’s Laws.

   In a collision, an object experiences a force
    for a specific amount of time which results in
    a change in momentum (the object's mass
    either speeds up or slows down).
   In a collision, objects experience an
    _______________; the impulse causes
    (and is equal to) the change in momentum.
     _______________ = force x time (greater the
      impulse, the greater the change in momentum)
   Observe that the _______________ the time
    over which the collision occurs, the
    _______________ the force acting upon the
    object.
   To minimize the effect of the force on an object
    involved in a collision, the time must be
    _______________;
   To maximize the effect of the force on an object
    involved in a collision, the time must be
    _______________.
Airbags in a Vehicle
   Air bags are used in automobiles because
    they are able to minimize the effect of the
    force on an object involved in a collision.
   Air bags accomplish this by extending the
    time required to stop the momentum of the
    driver and passenger.
   The same principle explains why dashboards
    are padded.
   When encountering a car collision, the driver and
    passenger tend to keep moving in accord with
    Newton's first law.
   Their motion carries them towards a windshield
    which results in a large force exerted over a
    short time in order to stop their momentum.
   If instead of hitting the windshield, the driver and
    passenger hit an air bag, then the time duration
    of the impact is increased.
   When hitting an object with some give such as
    an air bag, the time duration might be increased
    by a factor of 100.
   Increasing the time by a factor of 100 will result
    in a decrease in force by a factor of 100.
   This same principle of padding a potential
    impact area can be observed in gymnasiums
    (underneath the basketball hoops), in pole-
    vaulting pits, in baseball gloves and goalie
    mitts, on the fist of a boxer, inside the helmet
    of a football player, and on gymnastic mats.
Effects of Rebounding
   Occasionally when objects collide, they
    bounce off each other (as opposed to sticking
    to each other and traveling with the same
    speed after the collision).
   Bouncing off each other is known as
    _______________.
   Rebounding involves a change in direction of
    an object; the before- and after-collision
    direction is different.
   The importance of rebounding is critical to the
    outcome of automobile accidents.
   In an automobile accident, two cars can
    either collide and bounce off each other or
    collide and crumple together and travel
    together with the same speed after the
    collision.
   But which would be more damaging to the
    occupants of the automobiles - the
    rebounding of the cars or the crumpling up of
    the cars?
   Contrary to popular opinion, the crumpling up
    of cars is the safest type of automobile
    collision.
   If cars rebound upon collision, the momentum
    change will be larger and so will the impulse.
   A greater impulse will typically be associated
    with a bigger force.
   Occupants of automobiles would certainly
    prefer small forces upon their bodies during
    collisions.
   In fact, automobile designers and safety
    engineers have found ways to reduce the
    harm done to occupants of automobiles by
    designing cars which crumple upon impact.
   Automobiles are made with
    _______________.
       Crumple zones are sections in cars which are
        designed to crumple up when the car encounters
        a collision.
       Crumple zones minimize the effect of the force in
        an automobile collision in two ways.
   By crumpling, the car is less likely to rebound
    upon impact, thus minimizing the
    _______________ change and the
    _______________.
   Finally, the crumpling of the car lengthens the
    _______________ over which the car's
    momentum is changed; by increasing the
    time of the collision, the force of the collision
    is greatly reduced.
   1. Explain why it is difficult for a firefighter to
    hold a hose which ejects large amounts of
    high-speed water.
   Would you care to fire a rifle that has a bullet
    ten times as massive as the rifle?
No Seatbelt
   Cars are designed with
    crumple zones so they may
    slow down over a longer period
    of time, which keeps the force
    smaller. The crumple zone
    only slows the car more
    gradually. The only way it
    slows the occupants more
    gradually is if they are attached
    to the car. Stopping in a small
    amount of time means the
    force must be very large. This
    video clip shows some very
    dramatic scenes of car crash
    tests with test dummies who
    are not wearing seat
    belts. Specifically look for cars
    crumpling and people stopping
    in very small amounts of time.
With Seatbelt
   Seatbelts use two main
    ideas to protect passengers
    during a car
    accident. First, they slow
    the passenger down more
    slowly than the passenger
    running into steering wheel
    or dashboard. This keeps
    the force required to stop
    them smaller. It also
    prevents the person from
    contacting any of the glass
    windows in the car or
    continuing on to be stopped
    abruptly by the road, tree,
    or another automobile. The
    video clip shows the role of
    the seatbelt during an
    accident
   This clip clearly gives the
    driver a good reason to
    make sure occupants in the
    rear of the car are wearing
    their seat belts. Not
    wearing a seatbelt not only
    puts your life in danger but
    also anyone else who
    happens to be riding with
    you. The force from the
    seatbelt safely decelerates
    the driver, but the child in
    the back seat follows
    Newton's Law of Inertia and
    continues moving in the
    absence of a net force. The
    60mph "kid" not only breaks
    its own neck but also the
    neck of the driver.
   In this clip, we see that seat
    belts and child seats not
    only protect you in a frontal
    impact, they could also
    prevent a tragedy in rear
    end collision. In this clip,
    the station wagon literally
    gets accelerated out from
    under the "kids" sitting in
    the back. They were at rest
    originally, and in the
    absence of a net force (from
    the seat belt) they remained
    at rest while the car they
    were in was accelerated by
    the net force from the car
    that hit them. Newton's first
    law can be a killer!
Energy
   What is energy?
       The capacity to do _______________ or
        supply _______________.
       Energy is weightless, odorless, and tasteless.
       Energy is detected only because of its effects.


       Heat is _______________ that transfers
        between objects across a temperature change.
           Heat cannot be detected by the sense or by
            instruments – only changes caused by heat can be
            detected.
Potential Energy
   An object can store energy as the result of
    its position.

   This stored energy of position is referred to
    as potential energy.


   _______________ energy is the energy
    which an object has stored due to its
    position relative to some zero position.
Kinetic Energy

   _______________ energy is the energy of
    motion.

   An object which has motion - whether it be vertical
    or horizontal motion - has kinetic energy.

   Standard metric unit of measurement for kinetic
    energy is the Joule.
       1 Joule is equivalent to 1 kg  (m/s2).
   The amount of kinetic energy which an object
    has depends upon two variables:
     the _______________ (m) of the object

     the _______________ (v) of the object.
Sound Waves
Transverse Wave

   A _______________ wave is a wave in
    which particles of the medium move in a
    direction perpendicular to the direction which
    the wave moves.
Longitudinal Wave

   A _______________ wave is a wave in
    which particles of the medium move in a
    direction parallel to the direction which the
    wave moves.
Comparison of the Two
Surface Wave
   A _______________ wave is a wave in
    which particles of the medium undergo a
    circular motion. Surface waves are neither
    longitudinal nor transverse.

   Waves which travel along the surface of the
    oceans.
   Another way to categorize waves is on the
    basis of the ability (or nonability) to transmit
    _______________ through a
    _______________(i.e., empty space).

   Categorizing waves on this basis leads to two
    notable categories:
       electromagnetic waves
       mechanical waves.
Electromagnetic Waves
   An _______________ wave is a wave which is
    capable of transmitting its energy through a vacuum
    (i.e., empty space).

   Electromagnetic waves are produced by the
    vibration of electrons within atoms on the Sun's
    surface.

   These waves subsequently travel through the
    vacuum of outer space, subsequently reaching
    Earth.
   All _______________ waves are examples
    of electromagnetic waves.
Mechanical Waves
   A _______________ wave is a wave which is not
    capable of transmitting its energy through a vacuum.


   Mechanical waves require a _______________
    in order to transport their energy from one location
    to another.

   A sound wave is an example of a mechanical wave.
    Sound waves are incapable of traveling through a
    vacuum.
   Slinky waves, water waves, stadium waves,
    and telephone chord waves are other
    examples of mechanical waves; each
    requires some medium in order to exist.
       A slinky wave requires the coils of the slinky;
       a water wave requires water; a stadium wave
        requires fans in a stadium;
       and a telephone chord wave requires a telephone
        chord.
   _______________ is a wave which is
    created by vibrating objects and passed
    through a medium from one location to
    another.
       The medium is simply the material through which
        the disturbance is moving; it can be thought of as
        a series of interacting particles.
   A sound wave is similar in nature to a slinky
    wave.

       There is a medium which carries the disturbance
        from one location to another.
       Typically, this medium is air; though it could be
        any material such as water or steel.
   Regardless of what vibrating object is creating
    the sound wave, the particles of the medium
    through which the sound moves is vibrating in a
    back and forth motion at a given
    _______________.

   The frequency of a wave refers to how often the
    particles of the medium _______________
    when a wave passes through the medium.

   The frequency of a wave is measured as the
    number of complete back-and-forth vibrations
    of a particle of the medium per unit of time.
   A commonly used unit for frequency is the
    _______________ (abbrviated Hz), where

   1 Hertz = 1 vibration/second

   As a sound wave moves through a medium,
    each particle of the medium vibrates at the
    same frequency.
   The human ear is capable of detecting
    sound waves with a wide range of
    frequencies, ranging between
    approximately 20 Hz to 20 000 Hz.

   Any sound with a frequency below the
    audible range of hearing (less than 20
    Hz) is known as an _______________
    and any sound with a frequency above
    the audible range of hearing (more than
    20 000 Hz) is known as an
    _______________.
   Dogs can detect frequencies as low as
    approximately 50 Hz and as high as 45
    000 Hz.

   Cats can detect frequencies as low as
    approximately 45 Hz and as high as 85
    000 Hz.

   Bats, who are essentially blind and must
    rely on sound _______________ for
    navigation and hunting, can detect
    frequecies as high as 120 000 Hz.
   Dolphins can detect frequencies as high
    as 200 000 Hz.



   While dogs, cats, bats, and dolphins have
    an unusual ability to detect ultrasound, an
    elephant possesses the unusual ability to
    detect infrasound, having an audible
    range from approximately 5 Hz to
    approxmately 10 000 Hz.
   The sensations of these frequencies are
    commonly referred to as the
    ______________________________.

       A high pitch sound corresponds to a high
        frequency and a low pitch sound corresponds to a
        low frequency.
   The faintest sound which the human ear can
    detect is known as the _______________
    _______________.

   The most intense sound which the ear can
    safely detect without suffering any physical
    damage is more than one billion times more
    intense than the threshold of hearing.
   Since the range of intensities which the
    human ear can detect is so large, the
    scale which is frequently used by
    physicists to measure intensity is a scale
    based on multiples of 10.



   The scale for measuring intensity is the
    _______________.
           Source            Intensity Level

    Threshold of Hearing          0 dB
          (TOH)
      Rustling Leaves            10 dB

          Whisper                20 dB

    Normal Conversation          60 dB

     Busy Street Traffic         70 dB


      Vacuum Cleaner             80 dB

      Large Orchestra            98 dB

    Walkman at Maximum          100 dB
          Level
    Front Rows of Rock          110 dB
          Concert
     Threshold of Pain          130 dB

     Military Jet Takeoff       140 dB


    Instant Perforation of      160 dB
          Eardrum
   At normal atmospheric pressure and a
    temperature of 20ºC, a sound wave will travel at
    approximately 343 m/s; this is approximately
    equal to 750 miles/hour.

   While this speed may seem fast by human
    standards, the speed of a sound wave is slow in
    comparison to the speed of a light wave.

   Light travels through air at a speed of
    approximately 300 000 000 m/s; this is nearly
    900 000 times the speed of sound.
Breaking the sound barrier
   Accelerating past the speed of sound (750
    miles/hour)
   _______________ - range of velocities just
    below and above the speed of sound.
   When jets are in this transonic speed, they
    can create the vapor cone effect.
Light Waves
    "Is light a wave or a stream
    of particles?"



   The fact is that light exhibits behaviors which
    are characteristic of both waves and
    particles.
   All waves are known to undergo
    _______________ or the bouncing off of an
    obstacle.

   Most people are very accustomed to the fact that
    light waves also undergo _______________.

   The reflection of light waves off of a mirrored surface
    results in the formation of an image.
   A light wave is an _______________ wave
    which travels through the vacuum of outer
    space.

   Light waves are produced by vibrating
    electric charges.
   Electromagnetic waves exist with an
    enormous range of frequencies. This
    continuous range of frequencies is known as
    the
    ______________________________.

   The entire range of the spectrum is often
    broken into specific regions.
   Since this narrow band of wavelengths is the
    means by which humans see, we refer to it
    as the _______________ spectrum.

   Normally when we use the term "light," we
    are referring to a type of electromagnetic
    wave which stimulates the retina of our eyes.
   Each individual wavelength within the
    spectrum of visible light wavelengths is
    representative of a particular color.

   When light of that particular
    wavelength strikes the retina of our
    eye, we perceive that specific color
    sensation.
   Isaac Newton showed that light shining
    through a prism will be separated into its
    different wavelengths and will thus show the
    various colors that visible light is comprised
    of.

   The separation of visible light into its different
    colors is known as _______________.
   Dispersion of visible light produces the
    colors:
       red (R)
       orange (O)
       yellow (Y)
       green (G)
       blue (B)
       indigo (I)
       violet (V).

           It is because of this that visible light is sometimes
            referred to as ROY G BIV
   The red wavelengths of light are the
    _______________ wavelengths and the
    violet wavelengths of light are the
    _______________ wavelengths.

   When all the wavelengths of the visible light
    spectrum strike your eye at the same time,
    _______________ is perceived.

   Visible light is sometimes referred to as
    _______________.
   Technically speaking, white is not a color at
    all, but rather the combination of all the colors
    of the visible light spectrum.

   If all the wavelengths of the visible light
    spectrum give the appearance of white, then
    none of the wavelengths would lead to the
    appearance of black.
   Once more, black is not actually a color.

   Technically speaking, black is merely the
    absence of the wavelengths of the visible
    light spectrum.

   So when you are in a room with no lights and
    everything around you appears black, it
    means that there are no wavelengths of
    visible light striking your eye as you look at
    the surroundings.
   The color of an object is not actually within
    the object itself; rather, the color is in the light
    which shines upon it that ultimately becomes
    reflected or transmitted to our eyes.

   We know that the visible light spectrum
    consists of a range of frequencies, each of
    which corresponds to a specific color.
   When visible light strikes an object and a
    specific frequency becomes absorbed,
    that frequency of light will never make it to
    our eyes.

   Any visible light which strikes the object
    and becomes reflected or transmitted to
    our eyes will contribute to the color
    appearance of that object.

   So the color is not in the object itself, but
    in the light which strikes the object.
   The only role that the object plays is that it might
    contain atoms capable of absorbing one or more
    frequencies of the visible light which shine upon it.

   If an object absorbs all of the frequencies of visible
    light except for the frequency associated with green
    light, then the object will appear green.

   And if an object absorbs all of the frequencies of
    visible light except for the frequency associated with
    blue light, then the object will appear blue.
   When you look at an object and perceive a
    distinct color, you are not necessarily seeing a
    single frequency of light.

   Consider for instance that you are looking at a
    shirt and it appears purple to your eye.

   In such an instance, there my be several
    frequencies of light striking your eye with
    varying degrees of intensity; yet your eye-brain
    system interprets the frequencies which strike
    your eye and the shirt is decoded as being
    "purple."
Color Addition

   We have already learned that white is not a
    color at all, but rather the presence of all the
    frequencies of visible light – the entire
    spectrum of visible light.

   Combining the range of frequencies in the
    visible light spectrum is not the only means of
    producing white light.
   White light can also be produced by combining only
    _______________ distinct frequencies of light,
    provided that they are widely separated on the
    visible light spectrum.

   Any three colors (or frequencies) of light which
    produce white light when combined with the correct
    intensity are called _______________.
   The most common set of primary
    colors is
     _______________ (R)

     _______________ (G)

     _______________ (B)


       When red, green and blue light are
        mixed or added together with the proper
        intensity, white (W) light is obtained.
   Yellow (Y), magenta (M) and cyan (C) are
    sometimes referred to as
    _______________ colors of light since
    they are produced by the addition of equal
    intensities of two primary colors of light.
   Any two colors of light which produce white
    are said to be _______________ colors of
    each other.
       The complementary color of red light is cyan light.
        Since cyan light is the combination of blue and
        green light; and blue and green light when added
        to red light will produce white light.
       Thus, red light and cyan light (blue + green)
        represent a pair of complementary colors; they
        add together to produce white light.
Complementary Colors of
Light
   Red and Cyan

   Green and Magenta

   Blue and Yellow
Color Subtraction