Optics Flashcards
What is light
Both a particle and a wave
What is a medium
Any physical substance [air, water, dust] that acts as a carrier for the transmission of energy
What is a vacuum
Where there is absolutely no medium
What is our source of light
The sun
Does light need a medium to travel
No
What is light energy transferred through
Radiation
What is radiation
A method of energy transfer that does not require a medium. The energy that is transferred travels at the speed of light
What electromagnetic wave can the human eye detect
Visible light
What is Visible light composed of
All the colors of the rainbow
What distinguishes the colors of light
The different wavelengths
Which has a higher wavelength; left or right and of the spectrum
Right
How do we see color
Through rods and cones in our eyeballs
What does Rod do
Sensitive to all wavelengths of light a.k.a. colors, gives basic vision, responds to lower amounts of light [dim light ]
What do cones to
Response to high mountains of light [BriteLite], gives us color vision, there are three different types of cones which are each sensitive to different colors
What colors are cones sensitive to
Red, blue and green
What is a white light composed of
Different colors of light
How can they be produced
By combining only three colors; red green and blue
What are the primary colors for light
Red, blue and green
What happens if you mix to primary colors together
You get a secondary color
What happens when light hits an object
It can be absorbed, we can be bounced off the object a.k.a. reflected, or can be transmitted and changes directions in transparent objects aka. refraction
What is reflection
When light bounces off an object
What is refraction
When light changes directions in a transparent object
What is refraction
When light changes directions in a transparent object
What Is the subtractive color theory
If you subtract all the paint colors then you will get white…. Colors of objects we see depend on what colors of light reflected
How do we create color
By using pigments
What is a pigment
The chemical the apple of sort some colors of light reflect colours
How do pigments work
White light shines on and project in the pigments in that object absorbs some of the colors from the white light reflects the others
Tell how we can see that the grass is green
The grass absorbs the red and blue light and reflects the green light
What are the primary colors of pigment
Magenta, cyan, yellow
What are the secondary colors of pigment
Red blue and green
What are the secondary colors of light
Magenta, yellow and cyan
How do we get the color black
The object of colors
What is light
A form of energy
What is another name for light
Electromagnetically
What types of late can we see
White light and the visible spectrum
What colors is white light made up of
The colors of the rainbow
What is a wave
The disturbance that transfers energy from one point to another without transferring matter
What is the highest point in a wave called
The crest
What is the lowest place in a wave called
A Trough
What is the level between the crest in the trough of the wave called
The rest point
What is the symbol of a wavelength
A lembdu
What is the wavelength
The distance from one place in a wave to the next similar place in the wave
What is the wavelength
The distance from one place in a wave to the next similar place in the wave
What is amplitude
The wave height or depth from the rest position the lower the amplitude the longer the energy that is carried were transferred
What is frequency
The rate petition of a wave. The energy transferred depends on the frequency of the waves as well as the amplitude. The higher the frequency of the more energy is passed along the wave
What are the three main properties of waves
Wavelengths, amplitude and frequency
What is the frequency symbol
Hertz “Hz”
In simple words what is frequency
How many waves pass a point in one second
What is electromagnetic radiation
The wave pattern be able electric in magnetic fields that can travel through empty space.
What happens when the frequency increases
The wavelength decreases
Give the order of electromagnetic waves
Radio waves, microwaves, infrared visible spectrum, ultraviolet, x-rays, gamma rays
as you move up the spectrum, what happens to the frequency and wavelength
The frequency gets higher and the wavelength gets shorter
What is a prism
Transparent glass or plastic objects with flat sides
What is an optical illusion
When we see something that isn’t actually there
How are optical illusions creed
When differences occur between our perceptions or expectations and the image seen by the eye
What are the number one optical illusions caused by
Persistence of vision
How does persistence of vision work
Our eyes have “memory” so when the rods and cones in our highs see too much light, they get overloaded for example camera flash. When the light goes away they still send signals to the brain
What are optical illusion caused by atypical patterns
Our brain gets used to seeing images often and when we see images that are not typical, our brain gets confused and tries to fit the image we see with the typical images
What is refraction
The bending of light between two different substances, type of material can cause the light to change directions and cause the object to appear in different locations
What is an optical illusion caused by refraction
When light reflects and get scattered by different objects. When we see, our brain “knows” how lights works and make sense of what we are seeing’ for example rainbows
Do some colors of light bend more than others
Yes
Do some colors of light bend more than others
Yes, which is why they appear in different places
Describe the characteristics of images
Through salt; size, inversion, location, type
What is regular reflection
Reflection of light off a flat surface
What is diffuse reflection
Reflection of light off in a regular or double surface
What is an incident ray
Where the light comes from [the incoming Ray which meets the mirror at the point of incidents]
What is the angle of incidence
The angle between the incident ray and the normal
What is the normal
The imaginary line that is perpendicular to the mirror in all directions
What is the angle of reflection
The angle between the normal in the reflected ray
What is the reflected ray
Where the light reflects off
When does the angle of incidence equals the angle of reflection
On a normal flat plane mirror
What is the point of incidents
Where the incident ray and the reflected ray meet
What is a plane
Any flat surface
What is the first law of reflection
The angle of incidence is equal to the angle of reflection
What is the second law of reflection
The incident ray reflected ray of the normal are all coplanar [they sit in the same plane]
What does the symbol C stand for in the diagram of a curved mirror
The center of curvature
What is A rule for concave mirrors
Any incident ray and is parallel to the principal axes bull be reflected through the focus
What does the inside and the outside of a sphere produce
Inside produces a concave mirror and the outside produces a convex mirror
What are the parts of a concave mirror
C for the center of curvature, F for the focus, f for the focal length and V for the vertex
What is the principal axes in a spherical mirror
The line at which where it meets the mirror is a 90° angle
What are characteristic rays of concave mirrors
They can be used to predict what images will look like
What is a virtual image
An image in which light does not actually arrive or come from the image location
What is a virtual image
An image in which light does not actually arrive or come from the image location
Define transparent
When a material transmits all or almost all incident with light. These objects can be seen clearly through the material
What happens when my travels through a medium
Speed of light changes
What is light rays called when it is bent
refraction
What is refraction
The bending or change in direction of light when it travels from one medium to another
When light travels from here to glass or acrylic what will the angle of incidents be
Greater than the angle of refraction [only when coming in on an angle greater than 0°]
What happens when light travels from glass or acrylic to air
angle of refraction becomes more than the angle of incidence
The rules of refraction
Light bends towards the normal when the second medium is slower than the first medium and light bends away from the normal one light in the second medium is faster than the first
How do you calculate the index of refraction
By using Snells Law; n= sin <i></i>
Is the speed of light different for each medium
Yes but it is always less than the speed of light in a vacuum
What is index of refraction for a medium
Defined as the ratio of the speed of light in a vacuum to the speed of light in that medium
Does index of a fraction have a dimension
No it is a dimentionless quantity
What are the two different types of lenses
Convex and concave aka converging in diverging
For a convex lenses, what will rays coming in parallel to the principal axes do
refract through the principal focus
In convex lenses, what will raise going through the optical center do
Go straight through and have no refraction
What kinds of images will concave mirrors and convex lens show
Many types
What kind of images will concave lenses and convex mirrors show
Only one type of image
What kind of images will concave lenses and convex mirrors show
Only one type of image
What is a characteristic for concave lenses
Any incident ray parallel to the principal axis will refax as if it had passed to the principal focus
What is a critical angle?
When the angle of incidence produces a refracted angle of 90° but it only occurs when n1 is greater than n2
What is n equal to
The index of refraction and
How do you find the critical angle
sin-1 (n2/n1) or n1sinTheatai=n2sintheata2
What happens when an incident ray is less than the critical angle
It will refract normally
What happens if the incident ray is greater than the critical angle
It will have internal reflection and act the way a plane mirror does
What happens if H0 is positive
It’s above the principal axes and vice versa
What happens if H I is above the principal axis
The number is positive and vice versa
Is DO ever negative
No
When is DI a real image
What the number is positive and it’s a virtual image when the number is negative
What if F is positive number
But it is a converging lens and if it is a negative number it is a diverging lens
What if M is positive
Right image and if it is negative that it is an inverted image
