Chapter 15 Practice Questions
What type of signal [cell phone, TV, FM, AM] has the longest wavelength?
AM
What is the order of waves from lowest to highest frequency?
Radio waves, microwaves(a type of radio wave), infrared waves, visible light, ultraviolet waves, x rays, gamma rays
Television video signals are sent by ______ modulation.
amplitude
What is changed/modulated in an AM radio wave?
amplitude
Would the color blue or red have the shorter wavelength?
blue
A radio station broadcasts radio waves called_______, which have a specific frequency assigned to the station.
carrier waves
The image on an old television screen is produced by a_______.
cathode-ray tube
As the frequency of an electromagnetic wave decreases, its energy______.
decreases
What are gamma rays used for?
destroying harmful cells
Transverse waves that are produced by vibrating electric charges and consist of vibrating electric and magnetic fields are______.
electromagnetic waves
Electromagnetic waves carry______.
energy
What is ultraviolet light used in?
florescent materials
Which type of electromagnetic wave is the most energetic?
gamma rays
FM radio wave frequencies are_______than AM waves.
higher than
As the wavelength of an electromagnetic wave decreases, its frequency______.
increases
A remote control uses_______to communicate with the television set.
infrared waves
What are x rays used in?
medical imaging (bones, teeth, organs, etc...)
When gamma rays pass through living tissue they damage______.
molecules
To track a hurricane, meteorologists use_______.
radar
Electromagnetic waves transmit________.
radiant energy
Cell phones use______waves to transmit information.
radio
What type of electromagnetic wave has wavelengths greater than 1 mm?
radio waves
_______ are the type of electromagnetic waves often used for communication.
radio waves
What are radio waves used in?
radio, tv transmission
What are infrared waves used in?
remote controls
How would you describe x rays in terms of wavelength and frequency?
short wavelength, high frequency
What is the unit of radiant energy?
the electron
The ozone layer protects us from too much _____ radiation.
ultraviolet
If you stay outdoors too long, your skin might be burned by exposure to_______from the sun.
ultraviolet waves
Which type of electromagnetic wave enables skin cells to produce vitamin D?
ultraviolet waves
What is visible light used for?
vision
Each color of visible light has a different______.
wavelength