Simple Harmonic Motion: the Defining Relation and Its Graphs · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Motion that repeats itself

Science · Forces & Motion · ages 17-18
Name ______________________   Date ____________

  1. Where is velocity largest during one oscillation?

    • At the turning points
    • At the middle
    • Halfway in between

  2. Which rule defines simple harmonic motion?

    • Acceleration is proportional to displacement and points to the centre
    • Velocity stays constant
    • Acceleration points away from the centre

  3. In SHM, acceleration is largest at the extremes and zero at the centre. True or false?

    Circle one:   True   False

  4. A mass on a spring gets heavier while the spring stays the same. What happens to the period?

    • It gets longer
    • It gets shorter
    • It stays the same

  5. How do the displacement and acceleration graphs line up?

    • They are identical
    • They are unrelated
    • They are mirror images

  6. Which change alters the period of a simple pendulum swinging at small angles?

    • A heavier bob
    • A wider small swing
    • A longer string

  7. Which check proves a motion is simple harmonic?

    • Acceleration is proportional to displacement and points inward
    • Speed stays constant
    • Amplitude grows each cycle

  8. A pendulum is pulled a little further to the side and released. What happens to its period?

    • It gets longer
    • Unchanged
    • It gets shorter
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Answer key

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

Motion that repeats itself W1-mt_NTDayHkdfh-s1

  1. At the middle · The object shoots fastest through equilibrium, where displacement is zero.
  2. Acceleration is proportional to displacement and points to the centre · That single rule forces sine motion with a fixed period.
  3. True · Acceleration mirrors displacement, as the defining relation demands.
  4. It gets longer · Larger mass slows the oscillation, so each cycle takes longer.
  5. They are mirror images · Acceleration peaks where displacement peaks but points the opposite way.
  6. A longer string · Period answers to length and gravity, not to mass or small amplitudes.
  7. Acceleration is proportional to displacement and points inward · Testing acceleration against displacement is the direct test of the rule.
  8. Unchanged · Small swings stay simple harmonic, where period ignores amplitude.
Worksheet · LightMySky