The Electromagnetic Spectrum: Uses and Dangers · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

From radio waves to gamma rays

Science · Waves, Light & Sound · ages 15-16
Name ______________________   Date ____________

  1. What speed do all spectrum members share in empty space?

    • Radio fastest, gamma slowest
    • Gamma fastest, radio slowest
    • The same speed

  2. Which list gives the spectrum in order of rising frequency?

    • Radio, microwave, infrared, visible, ultraviolet, X-ray, gamma
    • Gamma, X-ray, ultraviolet, visible, infrared, microwave, radio
    • Visible, radio, gamma, microwave, X-ray, infrared, ultraviolet

  3. Which groups are ionising?

    • Radio, microwave and infrared
    • Ultraviolet, X-rays and gamma rays
    • Visible light only

  4. Why do microwaves suit cooking while radio waves do not?

    • Microwaves carry more heating energy in a handy band
    • Microwaves are ionising
    • Radio waves travel too fast

  5. Why are X-rays used to image bones?

    • They bounce off skin colour
    • They pass through soft tissue but are blocked more by bone
    • They warm the bone

  6. Gamma rays are used to sterilise medical tools.

    Circle one:   True   False

  7. Why does sunscreen matter in strong sun but not beside a radio?

    • Radios block all rays
    • Sunscreen cools the skin
    • Sunlight holds ionising ultraviolet, radio does not

  8. A student picks gamma rays to carry a phone signal. What is wrong?

    • Gamma travels too slowly
    • Gamma is ionising and dangerous, while radio suits signalling
    • Phones cannot use waves
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Answer key

For grown-ups. Fold this page away before handing over the rest.

From radio waves to gamma rays W1-mt_P_NXNSo1zQ-s1

  1. The same speed · Every member crosses space at one shared speed.
  2. Radio, microwave, infrared, visible, ultraviolet, X-ray, gamma · Radio is longest and gamma is shortest, with the rest between.
  3. Ultraviolet, X-rays and gamma rays · Danger starts where photons can ionise atoms.
  4. Microwaves carry more heating energy in a handy band · Each group earns its job from its properties.
  5. They pass through soft tissue but are blocked more by bone · Penetration differences draw the picture.
  6. True · High energy gamma kills microbes where heat cannot reach.
  7. Sunlight holds ionising ultraviolet, radio does not · Sunburn is an ionising ray warning.
  8. Gamma is ionising and dangerous, while radio suits signalling · Long low energy waves suit communication, not killer rays.
Worksheet · LightMySky