Wave Speed on a String from Tension and Linear Density · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

What sets the speed on a string

Science · Waves, Light & Sound · ages 18-19
Name ______________________   Date ____________

  1. A guitar string is tightened. What happens to its note?

    • It drops lower
    • It rises
    • It stays the same

  2. Which formula gives the string wave speed?

    • Square root of T over mu
    • T times mu
    • mu over T squared

  3. A bigger push makes the wave travel faster.

    Circle one:   True   False

  4. Tension is 100 newtons and mu is 0.25 kilograms per metre. What is v in metres per second?

    Answer: ______________

  5. A thicker string replaces a thin one at equal tension. What changes?

    • Pitch rises as v climbs
    • Nothing changes at all
    • Pitch drops as v falls

  6. The source plays higher while the string stays put. What sets the new wavelength?

    • v climbs with the source
    • lambda equals v over f with v unchanged
    • mu shrinks to help

  7. A student says plucking harder raises v. What is the error?

    • Tension always drops instead
    • Frequency owns the medium
    • Amplitude never enters the speed rule

  8. Tension grows four times on the same string. By what factor does v grow?

    • 2
    • 4
    • 16
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Answer key

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

What sets the speed on a string W1-mt_83x7vwb7UU-s1

  1. It rises · More tension speeds the wave, lifting the fixed length frequency.
  2. Square root of T over mu · Restoring tension over resisting inertia, square rooted, sets v.
  3. False · Amplitude never enters the speed rule.
  4. 20 · T over mu is 400, and its square root is 20.
  5. Pitch drops as v falls · Extra inertia per length slows the wave and lowers the note.
  6. lambda equals v over f with v unchanged · The medium guards v, so lambda must absorb the new f.
  7. Amplitude never enters the speed rule · How the wave was made cannot rewrite the medium properties.
  8. 2 · The square root halves the effect of the fourfold pull.
Worksheet · LightMySky