Wave properties & types · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Measuring and naming waves

Science · Waves, Light & Sound · ages 11-12
Name ______________________   Date ____________

  1. What name belongs to the lowest point of a repeating up-and-down wave?

    • Its crest
    • Its amplitude
    • Its wavelength
    • Its trough

  2. Light travels across a vacuum as a transverse wave. What oscillates in this wave?

    • Material particles of the vacuum
    • Electric and magnetic fields
    • Air particles carried from the Sun
    • Water particles moving in circles

  3. A symmetric wave's peak-to-trough height is 10 cm. What is its amplitude?

    • 5 cm
    • 10 cm
    • 20 cm
    • 0 cm

  4. Because a rope wave is transverse, it does not need a material medium.

    Circle one:   True   False

  5. Sound travels through air as compressions and expansions. Air particles vibrate parallel to the wave's travel. What type of wave is this?

    • Longitudinal
    • Transverse
    • Not a wave

  6. A wave moves at 32 m/s. Two neighbouring crests are at 1 m and 9 m along its travel. Find its frequency in Hz.

    Answer: ______________

  7. A wave has frequency 6 Hz and wavelength 2 m. Find its speed in m/s using v = fλ.

    Answer: ______________

  8. A wave's frequency stays fixed while its speed doubles. How does its wavelength change?

    • It becomes half as long
    • It stays the same length
    • It becomes twice as long
    • It becomes four times as long

  9. Speed stays fixed while frequency becomes three times its original value. What must happen to wavelength?

    • It becomes three times as long
    • It becomes one third as long
    • It stays at its original length
    • It becomes nine times as long

  10. A wave travels at 20 m/s with wavelength 4 m. Find its frequency in Hz.

    Answer: ______________

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Answer key

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

Measuring and naming waves W1-mt_LxK9OKZQZX-s1

  1. Its trough · The trough is the lowest point. The crest is the highest point.
  2. Electric and magnetic fields · Light is electromagnetic. Its fields oscillate; it does not require vibrating material in the vacuum.
  3. 5 cm · Peak-to-trough height is twice the amplitude. Half of 10 cm is 5 cm.
  4. False · The rope itself is the medium. Transverse describes the direction of vibration, not whether a medium is needed.
  5. Longitudinal · Parallel material vibration is longitudinal motion. This describes sound in air.
  6. 4 · The wavelength is 9 − 1 = 8 m. Frequency is 32 ÷ 8 = 4 Hz.
  7. 12 · v = 6 × 2 = 12 m/s.
  8. It becomes twice as long · With frequency fixed, λ = v ÷ f. Doubling speed doubles wavelength.
  9. It becomes one third as long · The product fλ stays fixed. Multiplying frequency by three requires dividing wavelength by three.
  10. 5 · f = v ÷ λ = 20 ÷ 4 = 5 Hz.
Worksheet · LightMySky