Grade 8 Science

Electromagnetic Spectrum

What is the Electromagnetic Spectrum

The Electromagnetic Spectrum is the spectrum where visible light energy

and all the invisible forms of radiant energy exist on the electromagnetic

spectrum.

Gamma Rays

- Gamma Rays have the shortest wavelength- While they have the shortest wavelength, they have the

highest energy- They result from nuclear reactions

X Rays

- The second shortest wavelengths- X Rays are good at penetrating tissue such as skin and

muscle- However, X Rays are absorbed by bones

Ultraviolet Radiation

- Ultraviolet Radiation is very energetic

- UV radiation comes from the sun

- It causes tanning, which is the skin’s

way of protecting itself

- It can damage the cornea, leading to

fogging in the cornea and causing a

slow loss of vision

Infrared Radiation

- A.K.A. heat radiation- Your eyes cannot see it, but your skin

can sense it- The hotter something is, the more

infrared rays it emits- Uses include motion sensors, burglar

alarms

Microwaves

- Microwaves have the second longest wavelengths

- This results in their lower energy- Microwaves use microwaves to heat

up objects- Microwaves use a specific

wavelength of microwaves that are absorbed by water particles. The waves cause the water particles to vibrate quickly and become hot

Radio Waves

- Radio waves have the longest

wavelengths and the lowest energy

of all the waves on the

electromagnetic spectrum

- Microwaves are a type of radio

waves

- Radio waves are used to broadcast

radio and television broadcasts

Visible Light

- Located to the right of the infrared waves and to the left of the ultraviolet waves

- The visible light spectrum consists of red (longest wavelength), orange, yellow, green, blue, indigo, and violet (shortest wavelength)

- The spectrum of visible light consists of a spectrum of wavelengths that range from approximately 700 nanometers (nm) to 400 nm

https://www.youtube.com/watch?v=jjy-eqWM38g