Electromagnetic Spectrum

Question 1

Radio Waves

Answer 1

• Longest wavelength
• Carry signals to phones, radios and TVs

Question 2

Microwaves

Answer 2

• Heat food, used for radar images

Question 3

Infrared Waves

Answer 3

• Infrared waves with longer waves can be detected as heat (these are called thermal or far infrared waves)
• The sun gives off shorter infrared waves (called near waves)
• Radiators or heaters give off infrared waves

Question 4

Visible Light

Answer 4

• The only electromagnetic waves we can see
• Each colour has a different wavelength
• Waves combine to make white light

Question 5

Ultraviolet Waves

Answer 5

• Purple-blue
• Humans can’t see them, some insects can
• Of the sun’s light, UV waves are responsible for sunburns

Question 6

X-Rays

Answer 6

• So powerful (so much energy) that they pass easily through skin
• Allows doctors to look at bones because X-rays can’t go through bones

Question 7

Gamma Rays

Answer 7

• Smallest wavelength, most energy
• Generated by radioactive atoms and in nuclear explosions
• Can kill living cells but are used to kill diseased cells when someone has cancer