# Electromagnetic Waves

## What Kind of Disturbance Creates an EM Wave?

Electromagnetic waves are formed by the vibrations of electric and magnetic fields. These fields are perpendicular to one another in the direction the wave is traveling. Once formed, this energy travels at the speed of light until further interaction with matter.

## How are EM waves Different from Mechanical Waves?

One way that electromagnetic waves are different from mechanical waves is that EM waves don’t need a medium to propagate while mechanical waves do. Furthermore, electromagnetic waves cannot transport energy while mechanical waves can.

## The Different Ranges of the EM Spectrum.

As you go up the electromagnetic spectrum the wavelength of the waves decrease but the frequencies and energies increase.

Radio- Radio wavelengths are longer than 1 mm. They have the longest wavelengths of the electromagnetic spectrum. For frequency they have the lowest frequency of 30 GHz to 300 kHz and they also have the lowest energy of less than .00001 eV.

Microwaves- Microwaves also have longer wavelengths of between .01-10 centimeters but low frequency of between 3-3000 GHz and low energy of .01-.00001 eV.

Infrared- The wavelength of infrared waves span from 710 nm to 1 millimeter. The frequency of infrared waves range from 3000-4300 GHz and the energy ranges from .01-2 eV.

Visible light- The wavelength of visible light waves falls between 400 and 700 nm. The frequency is between 4300-750000 GHz and the energy is between 2-3 eV.

Ultra-violet- The wavelength of ultra-violet waves are between 10 to 310 nm. The frequency is between 750000-300000000 GHZ and the energy goes from 3-100 eV.

X-Ray- The wavelength of x-rays range from 0.01 – 10 nm. The frequency ranges from 300000000- 30000000000 GHZ and the energy goes from 100-100,000 eV.

Gamma Ray- Gamma ray waves have the shortest wavelengths of less than 0.01 nanometers. Although gamma rays have the highest frequency of more than 30000000000 GHZ and the highest energy of more than a 100 keV.

## Ways Each Kind of Wave is Used Everyday.

Radio- Radio waves are used to transmit television programmes. Radio waves also transmit radio programmes so without them we could not listen to the radio or watch TV.

Microwave- Microwaves are used to heat up things inside the microwave. They are also needed to transmit calls between cellphones.

Infrared- Night vision goggles are able to detect humans at night because of the infrared light emitted by our skin. Infrared waves also helps us map the dust between stars.

Visible light- The reason that we can see color is because of visible light waves. Also, the things that are very common to us like lightbulbs and stars in the sky emit visible light.

Ultra-violet- The reason why our skin tans or burns is because the Sun emits ultra-violet radiation. Furthermore, ultra-violet radiation is used in sun beds to become tanner and in fluorescent lights.

X-Ray- X-Ray waves help doctors look inside someone’s body to check for any bone damage. X-rays are also used in industry to ensure that metal components or welds do not contain any cracks or damage.

Gamma Rays- Gamma rays are used to sterilise surgical instruments so without gamma rays harmful bacteria would be able to carry on from person to person. Gamma rays are also used to kill cancerous cells.

What Is The Electromagnetic Spectrum?