The Electromagnetic Spectrum

Question 1

Describe Radio Waves

Answer 1

Longest wavelength in the electromagnetic spectrum (up to a football field long)
Invisible to our eyes.

Question 2

Describe Microwaves

Answer 2

Invisible waves:

• heat our food
• transmit voice through thephone.
• can penetrate haze, clouds or smoke = is useful for transmitting information

Question 3

Describe Infrared

Answer 3

Lies between the visible and invisible portions of the electromagnetic spectrum.

• remote control uses infrared light to change the channel.
• Feel infrared via suns heat.
• Infrared photography can detect temperature differences.
• Snakes can detect infrared radiation, which is how they are able to locate warm-blooded prey in total darkness.

Question 4

Describe Visible Light

Answer 4

Only part of the electromagnetic spectrum we can see. - - Colour of rainbow = different wavelengths in this band of the spectrum.

• Thesun is a natural source of visible waves.
• When looking at an object, we see the colour of light reflected, and all other colours are absorbed.

Question 5

Describe Ultraviolet

Answer 5

Ultraviolet (UV)

• Humans can’t see
• sunburnt because of UV
• Atmosphere’s ozone layer blocks most UV rays.

Question 6

Describe X-rays

Answer 6

• Very high-energy light waves.
• Doctor use
• Naturally, occur in space. Can’t penetrate from outer space to theEarth’s surface.

Question 7

Describe Gamma Rays

Answer 7

• Most energy and shortest wavelength of the entire spectrum.
• Gamma rays generated by nuclear explosions and radioactiveatoms.
• Gamma rays can kill livingcells
• Medical professionals sometimes use them to destroy cancerous cells.
• In deep space, gamma-ray bursts occur daily.

Question 8

Order waves from shortest wavelength to longest wavelength

Answer 8

RMIVUXG

radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, gamma rays

Question 9

What is electromagnetic radiation?

Answer 9

A stream of photons (bundles of light energy), travelling in waves.
They carry transverse vibrations in electrical and magnetic fields.

Question 10

Why is electromagnetic radiation different to other types of waves?

Answer 10

It does not need matter to travel through - can travel through empty space (a vacuum).

Question 11

How does the spectrum rank different forms of electromagnetic radiation?

Answer 11

Lowest energy and longest wavelength to highest energy to shortest wavelength.