The Electromagnetic System

Electromagnetic System

The opposite range of different wavelengths that compose Electromagnetic radiation.

Radio Waves

• Longest wavelengths

• Lowest frequencies

• Use on earth: transmits radio/Tv signals

• Scientific use: to study the composition, structure, and motion of celestial objects

Microwaves

• 2nd longest wavelengths

• Low frequencies

• Use on earth: Microwave ovens, cell phones, wifi, and bluetooth

• Scientific use: to learn about the galaxies and stars that are behind clouds of dust

Infrared

• Means “below red”

• Lower frequency/ longer wavelength than visible red

• 2 types:

  Heat from Sun; used in toaster ovens/grills

  Used in remote controls

• Scientific use: to map out dust between stars

Visible Light

• Only part in spectrum we can see

• Red(longest)

• Purple(shortest)

• Radiated as white light but can be separated into different colors

• Scientific use: to study the composition of objects of the universe

• Determine: size, temp, age of stars

Ultraviolet

• Shorter wavelengths/ higher frequency than visible light

• Found naturally in sunlight; causes sunburn & cancer

• Scientific use: to study very hot areas of universe like center of galaxies

• Newly formed stars emit lots for study of structure/evolution

X-rays

• 2nd shortest wavelengths/ high frequencies

• Makes images of bodies

• Scientific use: to study events that are hotter/more energetic than other stars

• Neutron stars emit X-rays

• Emitted by supernovas to find blackholes

• Structure and evolution of the universe

Gamma Rays

• Shortest wavelengths/highest frequencies & energies

• Produced: power generations

• Radioactive/causes and treats cancer

• Solar flares cause gamma rays

• Scientific use: to study high energy in universe/the origin and how far it expands

Electromagnetic waves transfer from one place to another.

Energy

As frequency increases, wavelength .

decreases

As frequency decreases, wavelength .

increases

Shorter Wavelengths = ___________ __________.

Higher energy

Transferse (i don’t think that’s spelled correctly)

Electromagnetic waves & vibrations are at right angles at direction of travel.

All electromagnetic waves travel through space at the _________ ___ _______.

Speed of light

How many m/s is the speed of light?

300,000,000 m/s

Lightyear

The distance the speed of light travels in 1 year (9.5 million km)

The EMS contains types of radiation by…?

Wavelengths, frequency, and energy

The Doppler Effect (Redshift)

Describes wavelengths of energy shift as objects move.

As objects move toward you toward you, waves become _______________.

compressed

• (Sound: higher; color: blue)

As objects move away, waves become _____________.

stretched

• (Sound: lower; color: red)

Edwin Hubble

• Noticed galaxies we see from Earth experience redshift; therefore, must move away from Earth

If objects move away…

Universe expands

By __________, scientists determine ______ at which star is moving & calculates distances from Earth

Redshift; speed

Why are Gamma Rays so dangerous and damaging?

• They generate an overwhelming amount of energy

• Short wavelength