Light Flashcards
____ - A self-propagating TRANSVERSE wave that consists of mutually supporting electric and magnetic fields (also known as electromagnetic radiation)
Light
Since light is self-propagating, it can travel in a _____
Vacuum
____ ____ travel at approximately 3 x 10^8 m/s in a VACUUM
Light waves
Instead of v we use _ in the speed of light. So c = f(wavelength)
c
The wavelength of a light wave is usually measured in _____
Nanometers (nm)
_ nanometer = 1x10^-9 meters
1 nanometer (Ex: 500 meters x 1x10^-9)
When light waves travel from one medium to another the speed ____ but the frequency ___
Changes
Stays the same
Since c = f(wavelength) and this means that wavelength also ____
Changes
Light moves on its own so as density increases, the speed of light ____
Decreases
Light waves travel faster through __ than ___ and ___
Air
Than liquids and solids
In the EM spectrum all light waves travel at the ___ speed but the light wavelength, frequency, and energy vary
Same
Purple light has the ____ frequency and ___ wavelength
Highest frequency
Shortest wavelength
Red has the ___ frequency and the ___ wavelength
Lowest frequency
Longest wavelength
The wavelengths of ____ ___ range is 400-700 nm
Visible light range
Gamma rays have the ____ wavelength
Shortest wavelength
Radio waves have the _____ wavelength
Longest wavelength
____ - The slight bending of light as it passes an edge of an obstacle or an aperture (slit or small opening. Size depends on how much the light bends)
Diffraction
The smaller the size of the slit, the ____ light bends
Less
The larger the size of the slit is the __ the light bends
More
The ____ slit provides two coherent monochromatic sources that produce an interference pattern of light and dark bands or spots
Double slit
The more slits, the ____ spots in between the light
More
Light is ____ if it hits a surface and bounces off rather than being transmitted through
Reflected
____ (____) reflection- reflection off a smooth surface. (Sun reflecting off water as itself)
Plane (Spectacular) Reflection
____ reflection - Reflection of light into many directions by rough surfaces. (Sun reflecting off water with many ripples. Goes in many different directions)
Diffuse reflection
___ __ ____ - States the angle of incidence is equal to the angle of reflection
Law of reflection
in ALL optics problems the angles are measured from the ___, - A perpendicular line from the surface at the point of incidence (contact)
Normal
___ - The bending of light as it travels from one medium to the next
Refraction
The way in which light ___ when it enters a new medium is not only material dependent, but also frequency dependent
Refracts
____ frequencies refract more, this means violet light bends more than red light
Higher frequency
____ - The spreading out of light according to color (Ex: The prism)
Dispersion
___ light is refracted predominantly at 42.5 degrees. (The light reaching your eye comes from higher drops in the sky)
Red
____ light is refracted predominantly at 40.8 degrees. (The light reaching your eye comes from lower drops in the sky)
Violet
___ light is the combination of all colors of the visible light spectrum
White light
The three primary colors of light are
Red, Green, and blue
____ - A material which selectively absorbs certain wavelengths of light and then reflects other wavelengths. (Primary colors are yellow, cyan, and magenta. They make black)
Pigment
Light is ____ and pigments are ___ in terms of color
Additive
Subtractive
Red filter causes it to ___ all colors but red
Absorb
____ light vibrates in every direction
Natural light
____ light vibrates in one specific plane
Polarized light
We can ___ light by using a filter with small slits that filter light polarized in other dimensions
Polarize
Polarization reduces ____
Glare
_____ - The ability to see through something clearly
Transparent
____ - The ability to partially see through a material
Translucent
____ - Not being able to see through a material
Opaque
light changes ___ it changes media. This change in ___ causes light to change its direction
Speed
___ ____ ____ (n)- The ratio of the speed of light in a vacuum compared to the speed of light in the medium
Index of refraction (n)
_ = speed of light in vacuum 3x10^8m/s
c
_ = speed of light in new medium (m/s)
v
Since the speed of light slows down in media besides vacuum, “n” will always be ___ than or equal to 1
Greater than
We will approximate the “n” of air to be _
1
___ ___ - An equation that relates the angle of the incidence of light and the angle of refraction of light at the interface of two different mediums
Snell’s law
When light travels into a medium with a __ index of refraction, it bends TOWARDS the normal
higher
When light travels into a ____ index of refraction, it bends AWAY from the normal
Lower
If nr > ni the refracted ray is bending ___ the normal
Toward
If ni > nr the refracted ray is bending ___ from the normal
AWAY
If you cross a vertical (up and down) polarizing lens with a horizontal (left and right) polarizing lens what happens to the light through both lenses?
No light penetrates through both lenses
What 3 color cones do we have in our eyes
Red green blue
What wave properties are involved in the double slit experiment?
Diffraction and interference
Two complementary colors of light (Red and cyan) are mixed together to give which color light?
White
EXAMPLE OF HAVING ONLY 1 DEGREE
nair sin 35 = nwater sin 02
1.00029 sin 35 = 1.33 sin 02
Solve the first sin
Divide both sides by 1.33
0.4314 = sin 02
sin ^-1 (press shift button to get negative sin) (0.4314) = 02
02 = 25.6 degrees
