Unit 4
Quiz yourself by thinking what should be in
each of the black spaces below before clicking
on it to display the answer.
Help!
|
|
||||
|---|---|---|---|---|---|
| Vibration | a back and forth motion that repeats itself.
🗑
|
||||
| Waves | the disturbance made by the vibration
can be many mediums for travel
water
solids
air
longitudinal wave
transverse wave
🗑
|
||||
| LONGITUDINAL WAVE | disturbance that causes particles to move closer together or farther apart in the same direction that the wave is moving.
🗑
|
||||
| TRANSVERSE WAVE | disturbance that causes motion that is perpendicular to the direction that the wave is moving.
🗑
|
||||
| AMPLITUDE | displacement from rest to the crest or from rest to the trough.
🗑
|
||||
| PERIOD | (T) time for the wave to repeat itself.
🗑
|
||||
| WAVELENGTH | (cm or meters) is length in which wave repeats itself.
🗑
|
||||
| CREST | maximum disturbance from rest
🗑
|
||||
| TROUGH | maximum disturbance in the opposite direction from rest.
🗑
|
||||
| electromagnetic spectrum | waves with both electric and magnetic properties.
are produced by accelerating electric charges, such as an electron oscillating in harmonic motion.
🗑
|
||||
| What does the electromagnetic spectrum include? | The spectrum contains visible light
Lower frequencies
radio waves (low frequency) (TV)
ex: infrared waves (heat food)
Higher frequencies (more energy)
ultraviolet waves (burn your skin!)
high frequency X rays (medical uses)
gamma rays
🗑
|
||||
| How do the waves differ? | The wavelengths visible to our eyes constitute only a thin portion of the electromagnetic spectrum.
49% of sun’s radiant energy is visible
46% is infrared
rest is ultraviolet.
radiant energy comes from the sun as photons
🗑
|
||||
| How does light relate to energy? | When light hits an object:
some energy is absorbed
some energy is reflected
Atoms can absorb only those waves whose energy would move them to a possible energy state for the atoms.
🗑
|
||||
| What is visible light? | Visible light is only a tiny portion of the EM spectrum.
ranges from 400 - 750 nanometers
red, orange, yellow, green, blue, indigo, violet
[red, yellow, green, cyan, blue & magenta]
can be bent…reflected, refracted, transmitted and absorbed
🗑
|
||||
| How does light produce color? | Each element has a different set of wavelengths it can absorb
Clear transparent objects don’t have the right wave lengths for any visible light of any color
Color is a function of the photons the object does not absorb
It may transmit or reflect photon
🗑
|
||||
| What are photons? | the energy in a light wave of a given frequency is a specific amount of energy.
each photon has an energy (E) that is related to the frequency of light.
connects both the light wave/light particle theories.
light is a stream of moving photons.
🗑
|
||||
| What is reflection? | light travels in a straight line from its source until it encounters some object or particles of matter
rays reflected from a perfectly smooth surface are parallel to each other
rays reflected from a rough surface causes rays to travel in random directi
🗑
|
||||
| How does reflection happen? | can think of light as “bouncing” off a surface.
it actually is more complex.
think in terms of light rays, so we can use the Law of Reflection.
“The angle of incident is equal to the angle of reflection” when in the same plane.
🗑
|
||||
| Is there one ray from each object? | only three lines are usually shown.
The incident ray
The reflected ray
And a line called “normal”
🗑
|
||||
| What is refraction? | a change in direction of a light ray when it moves through different transparent materials.
results from a change in speed when light passes from one transparent material to the next.
🗑
|
||||
| What is light absorption? | Materials can be classified as to how much of the light falling on them is reflected
Opaque objects reflect light, absorb light or do a combination
Absorbed light gives up its energy to the material,may be remitted at a different wavelength or temperatu
🗑
|
||||
| What is diffraction? | the bending of light around the edge of an opaque object.
the determining factor is the size of the opening (or obstacle) compared to the wavelength.
🗑
|
||||
| White light | a mixture of all visible frequencies. (just need red, green, blue)
🗑
|
||||
| Primary (additive) colors | red, green and blue.
🗑
|
||||
| Complementary colors | (mixture of additive primaries) are cyan (turquoise), yellow, and magenta (purplish red).
🗑
|
||||
| yellow | red + green
🗑
|
||||
| cyan | green + blue
🗑
|
||||
| magenta | blue + red
🗑
|
||||
| What is subtractive mixing? | Subtractive refers to situations where the mixture is made from light absorbing pigments (paint or computer printer).
Primary subtractive pigments are cyan, magenta, and yellow (check your printer).
Paint stores call these blue (cyan), red and yellow.
🗑
|
||||
| subtractive colors | Cyan, Magenta and Yellow
🗑
|
Review the information in the table. When you are ready to quiz yourself you can hide individual columns or the entire table. Then you can click on the empty cells to reveal the answer. Try to recall what will be displayed before clicking the empty cell.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Created by:
rldickerson08@aol.com
Popular Science sets