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What does it mean for light to interact with matter?
The interaction of light and matter determines the appearance of everything around us.
What is refraction?
Refraction is the bending of light when it enters from one medium into another.
When light enters a different material, does its frequency change?
No. The frequency of light does not change. The frequency of light is determined by how this light was created.
Yes. Light travels at different speed in different materials.
When light enters a different material, does its speed change?
When light enters a different material, does its wavelength change?
Yes. As the light goes from one material into another:
If the wavelength of light changes when it enters a different material, does its color change?
No. The colors we see are determined by the frequency of light, and not the wavelength.
Which inventions are based on refraction?
Lenses use refraction to bend and focus light, creating an image. Lenses are used in many technologies, including eye glasses, microscopes, telescopes, cameras, and binoculars.
Why does a prism bend and separate light?
In math, a *prism* is a geometrical solid object whose two end faces are similar, equal, and parallel rectilinear figures. The sides of a prism are parallelograms. The type of prism used to separate w…
What is the *index of refraction*?
The index of refraction in a medium is defined as
The index of refraction of a medium depends on:
Which factors determine the index of refraction of a medium?
What is dispersion?
Dispersion is the spreading out of refracted light according to color.
refraction
a wave is bent due to a change in speed
Optical Illusions
When you look under water, the light does not travel in a straight line. This is an optical illusion. It only happens when the light refracts.
medium/media
A substance through which a wave can travel.
Color separation
White light turning into ROY G BIV. Example, refraction is responsible for rainbows.
lens
...a curved piece of glass or other transparent material that refracts light.
focal point
..., the point at which light rays parallel to the optical axis meet when reflected or refracted
Focal Length
Sign Conventions for Lenses
convex lens
..., a lens that is thicker in the middle than at the edges
real image
`, an image of an object formed by light rays that actually come together at a specific location
virtual image
a reflected optical image; see "inverted image"
concave lens
..., a lens that is thinner in the middle than at the edges
Animal eyes
mainly convex lenses, and are eyes
Optical instruments
things that help people make observations.
cameras
an optical instrument that is used to record images
telescopes
an optical instrument that is used to see things at a far distance
light microscopes
an optical instrument that us used to see things close up even closer
Summary
/ Refraction of light can create optical illusions and can separate white light into different colors/ lenses form images by refracting light, convex lenses produce both real image and virtual images/ a magnifying glass and the lens of the human eye are convex lens/ concave lenses produce only virtual images/ Cameras, telescopes, and microscope are optical instruments that use lenses to form images"
How does light travel in straight lines?
Light travels in straight lines if the medium through which the light travels does not change
How are optical illusions created
they are created through refraction of light
What three optical phenomena come from refraction of light?
optical illusions, images being formed by lenses, and white light being separated into different colors
animal eyes, and magnifying glasses
What are 2 examples of convex lenses
cameras, telescopes, and microscopes
What are 3 examples of concave lenses
100x
what is the magnification given by a 5x lens used with a 20x lens
What's the difference between a digital camera and a 35 mm camera
a 35mm camera has a film, and a digital camera has light sensors
prism
a piece of glass that separates white light into ROY G BIV
materials
When a wave reaches a boundary between two _______, some wave bounces back into the first material. The return of a wave back into its original material is called reflection.
bounces
When a wave reaches a boundary between two materials, some wave _______ back into the first material. The return of a wave back into its original material is called reflection.
reflection
a wave strikes a boundary and bounces back
reflected
Usually waves are partly _______ and partly refracted when they fall on a transparent material.
refracted
Usually waves are partly reflected and partly _______ when they fall on a transparent material.
partly
Usually waves are _______ reflected and _______ refracted when they fall on a transparent material.
Transparent
All light passes through; can see through clearly eg. glass
angle
When a wave that is traveling at an _______ changes its speed upon crossing a boundary between two materials, it bends. This bending is called refraction.
Speed
Units: cm/s, m/s, mi/hr, km/s ...
boundary
When a wave that is traveling at an angle changes its speed upon crossing a _______ between two materials, it bends. This bending is called refraction.
bends
When a wave that is traveling at an angle changes its speed upon crossing a boundary between two materials, it _______. This bending is called refraction.
light
small portion of the electromagnetic spectrum that our eyes are capable of seeing
material
Refraction is caused by changes in the speed of light as it passes from one _______ to another.
Decreases
A freight car moves along a frictionless level railroad
toward
2.rule of refraction
Normal
A line drawn at right angles to the reflecting surface at the point where the incidence ray hits; All angles are measured from here
Increases
As temperature increases, the vapor pressure of a liquid _______.
away from
When light rays enter a material in which their speed increases, the rays bend _______ normal.
more
a light object with a large surface area is (more/less) affected by the drag force than a more compact object is when both objects are falling
direction
A point toward something, determined by its orientation and sense.
measured
The angle of incidence and angle of refraction are both _______ from the normal
possibly
Light travels as fast as it can _______ go in air. This speed is 300 million m/s, and is labeled c.
300 million m/s
Light travels as fast as it can possibly go in air. This speed is _______, and is labeled c.
C
The specific heat capacity in J/g K
index
The _______ of refraction n is defined as , where c is the speed of light in air, and v is the speed of light in a material.
n=c/v
The index of refraction n is defined as _______, where c is the speed of light in air, and v is the speed of light in a material.
v
The index of refraction n is defined as , where c is the speed of light in air, and _______ is the speed of light in a material.
Property
a macroscopic characteristic of a system that is independent of path (or process)