Electrical and Magnetic disturbance that moves through space at the speed of light. (They can travel through empty space)
* Oscillations may occur at very low frequency or at an extremely high frequency and the entire range of frequencies is referred to as...
* EM waves are often classified by frequency in a scheme called...
The _____ of the wave produced is the number of complete vibrations per second.
frequency and speed
The wavelength of an EM wave depends on its_______.
frequency and wavelength
The waves differ in the way they are produced and interact with matter and from each other in their _____ and _____
Each type of wave occupies a particular range of wavelengths known as...
A throbbing pulse of electromagnetic radiation is called...
longest wavelengths and shortest frequencies in the EM Spectrum. Used to transmit radio and television signal
Global Positioning Systems (GPS)
measure the time it takes a radio wave to travel from several satellites to the receiver, determining the distance to each satellite.
AM Radio Waves
A type of radio wave that readily bends around buildings and other objects that might be present in their path. (180-550 meters)
FM Radio Waves
Type of radio wave that has a shorter wavelength than the AM waves (2.8-3.4 meters)
A rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents that carry radio signals
As early as the 1790s, the first semaphore system (visual telegraphy) was developed in ___
Sir Charles Wheatstone and Sir William Fothergill Cook
They constructed the first commercial electrical telegraph in England
Alexander Graham Bell
In 1876, the conventional telephone was invented by ___
Scottish Inventor John Logie Baird obtained a device that is known as the ___, which was the basis of semi-experimental broadcasts done by the British Broadcasting Corporation beginning ing September 30, 1929
They are basically extremely high frequency radio waves and have the shortest wavelengths . They have very short wavelengths ranging from approximately 1 millimeter to 30 centimeters
RADAR (Radio Detection and Ranging)
Used to find the speed of an object by sending out radio waves and measuring the time it takes them to return.
Sir William Herschel
In 1800, he discovered the existence of infrared by passing sunlight through a prism
EM radiation with a wavelength longer than that of visible light. Microscopically, ______ is typically emitted or absorbed by molecules when they change their rotational-vibrational movements
a picture that shows regions of different temperatures in the body. Temperatures are calculated by the amount of infrared radiation given off.
Near Infrared Light
The closest in wavelength to the visible light
Far Infrared Light
Type of Infrared which is closer to the microwave region of the EM spectrum
Determining the temperature of objects
Portion of the EM spectrum that is visible to the human eye. (Higher frequency than Infrared rays) Longest wavelength= red light shortest wavelength= violet (purple) light
EM radiation with a wavelength shorter than that of visible light, but longer than x-rays (carry more energy)
This is produced by high-temperature surfaces, such as the sun.
High-energy waves which have great penetrating power and are used extensively in medical applications and in inspecting wields (Shorter wavelength and higher frequency than UV-rays)
In many languages, X-radiation is called ___
Wilhelm Conrad Rontgen
The person who named it the Rontgen Radiation to signify an unknown type of radiation
Generated by radioactive atoms and in nuclear explosions, and are used in many medical applications.
Gamma Knife Surgery
A procedure wherein multiple concentrated beams of gamma rays are directed on the growth in order to kill cancerous cells
Energy produced by nuclear reactions at the core of the sun
Are the visible radiation we call sunlight.
Most of the sun's energy is released in these_
The radiation given off from the sun is what we called_
Can be defined as the process of emitting energy by any particles, such as in the case of high-energy, protons, neutrons, atoms, and ions;, and waves, either light or sound,
Are composed of unstable atoms that give off its excess energy until it becomes stable
Happens during the spontaneous change of an atom to be more stable
An especially damaging form of radiation which can create electrically charged ions in the material it strikes
Break apart atoms and molecules, causing severe damage in living organism
Basic unit used to measure exposure to ionizing radiation
Millisieverts or microsieverts
Radiation exposure is expressed in _
An average person is exposed to ___ of whole body exposure per year from all sources