Chapters 11,12,13 Flashcards
Photon
Mass-less energy particle that make up light
Electromagnetic wave
Created by vibrating electric charges- moves through a vacuum
Gamma ray
Emitted from a decaying atomic nucleus 100 trillionths of a meter
Infrared wave
Waves that change to heat when absorbed 1mm to 700 billionths of a meter
Microwave
Wavelengths range from .1mm to 30 cm
Radio wave
Used for communication. Wavelengths are longer than 10 cm
Ultraviolet wave
EM wave with wavelength between 400 billionths and 10 billionths of a meter
Visible light
Can be detected by the human eye 700 to 400 billionths of a meter
X-Ray
Used for medical imaging 10 billionth of a meter to 10 trillionths of a meter
Analog signal
An electric signal whose values change over time
Carrier wave
Specific frequency that a radio station is assigned and uses to broadcasts signals
Digital signal
An electric signal with only two possible values
Modulation
Process of adding a signal to a carrier wave by altering the carrier waves amplitude
Transceiver
Device that transmits radio signals at one frequency and receives radio signals at a different frequency
GPS
A system of satellites and ground monitoring stations that enable a receiver to determine its location at or above the earths surface
Compare and contrast sound waves and electromagnetic waves
Sound waves require and medium, and are compressional
Electromagnetic waves are produced by vibration
How are moving electric charges related to electric and magnetic Fields?
They both have surrounding electric and magnetic fields. They exert a force even when the on ejecting in contact
What is radiant energy?
Energy carried by an electromagnetic wave, it helps by heating the earth
What is the speed of a vacuum, air,and water?
Vacuum- 300,000 km/s
Air-299,000 km/s
Water- 226,000 km/s
How are wavelength, frequency, intensity, and energy related in a electromagnetic wave?
All waves have wavelengths, frequencies, and intensities. As the frequency increases wavelengths become smaller
The range of frequencies in which electromagnetic waves occur is called ..?
Electromagnetic spectrum
Radio waves make what vibrate?
Electrons
What is used in magnetic resonance imaging to help map body tissues?
X-rays
What is absorbed by the ozone layer?
Ultraviolet waves
Radio waves with wavelengths of less than 1mm are what?
Microwaves
Warmth that you feel from a fire is transmitted to you by?
Infrared waves
The range of electormagnetic waves that you can detect with your eyes?
Visible light
What are two uses for a GPS?
Navigational and determining your exact location
Why is satellite telephone service best for one-way communication?
If the satellite telephone were a two way then there would be delays, caused by large distances the signals traveled.
Coherent light
Device that reads intensities of reflected light and converts the info to digital signals
Filter
Transparent material that selectively transmits light
Fluorescent light
Light generated by using phosphorus to convert ultraviolet light to visible light
Holography
Technique that produces a complete three dimensional photographic image of an image
Incandescent light
Light that is produced by heating a piece of metal
Incoherent light
Light that can contain more than one wavelength, travel in more than one direction
Index of refraction
Property of a material indicating how much the speed of light is reduced in the material compared to its papered In a vacuum
Linearly polarized light
Light whose magnetic field vibrates in only one direction
Mirage
Image of a distant object produced by refraction of light through air layers of different densities
Opaque
Material that absorbs or reflects light, and doesn’t transmit any though it
Optical scanner
Device that reads intensities of reflected light and convert the info to digital signals
Pigment
Colored material used to change the color of other substances
Total infernal reflection
The complete reflection of light at a boundary that occurs when light strikes an angle greater than the critical angle
Translucent
Material that transmits/scatters light, produces blurry images
Transparent
Material that transmits light without scattering the light waves
Why are polarized sunglasses popular among people who like to fish?
When the light is reflected some of it is polarized with the magnetic filed vibrating vertically and block the reflected light, reducing the glare
Why are optical fibers often called light pipes?
Because they act as small pipes that allow ligh to pass through them
Why are sunsets and sunrises sometimes red?
The red cone in your eye adjusts to what it sees, and that is the colors red and yellow
Name four different types of light?
Coherent, incandescent, incoherent, and fluorescent
What is a polarizing filter?
A special filter with lines of crystals that Act as a group of parallel slits
Plane mirror
Flat smooth surface that reflects light to form upright, virtual images
Virtual image
An image formed by diverging light rays that is perceived by the brain, even though the images do not actually originate form where they are being projected
Concave mirror
A reflective surface that curves inward, and can magnify objects or create real images
Optical axis
Imaginary straight line that is perpendicular to the surface at the center of a mirror or light
Focal point
Location on the optical axis of ad curved mirror or lens where light rays that are initially parallel to the optical axis converge after they strike the mirror or lens
Focal length
Distance from the center of a lens or mirror to the focal point
Real image
An image that appears at a certain location as a result of rays of light converging at that location
Convex mirror
A reflective surface that curves outward, away from the viewer, and forms a reduced upright virtual image
Concave lens
A lens that is thicker in the middle than on the edges
Concave lens
A lens that is thicker on the edges than in the middle
Cornea
Transparent outer layer covering of the eye ball
Retina
Inner lining of the eye that has cells
Refracting telescope
Uses lenses to gather and focus light form distant objects
Reflecting telescope
Uses mirrors and lenses to collect and focus light from distant objects
Microscope
Instrument that uses two or more convex lenses
Converging rays
Light rays that move closer together as they travel
Diverging rays
Light rays that move apart from each other as they travel
What are the highest to lowest types of waves?
Gamma rays, X-ray, ultraviolet waves, visible light, infrared waves, microwaves, and radio waves
