Practice Flashcards
Flip to reveal answersWhat shape are the x, v and a graphs of an SHM oscillator against time?
Track your progress — Sign up free to save your progress and get smart review reminders based on spaced repetition.
All 17 Flashcards — SHM graphs, phase and timing
Sign up free to track progress and get spaced-repetition review schedules.
Question
What shape are the x, v and a graphs of an SHM oscillator against time?
Answer
All three are **sinusoids** (smooth waves), but **shifted** in phase relative to one another.
Question
What is the phase relationship between velocity and displacement in SHM?
Answer
Velocity **leads** displacement by a **quarter-cycle (90°)** — v is biggest at the centre, zero at the ends.
Question
What is the phase relationship between acceleration and displacement in SHM?
Answer
They are **antiphase (180° apart)** — a is the mirror image of x. This is the rule **a = -ω²x**.
Question
Where is the velocity of an SHM oscillator greatest?
Answer
At the **centre** (equilibrium, x = 0). It is **zero** at the turning points (maximum displacement).
Question
Where is the acceleration of an SHM oscillator greatest?
Answer
At the **turning points** (maximum displacement). It is **zero** at the centre, because a = -ω²x.
Question
What does the minus sign in a = -ω²x mean?
Answer
The acceleration always points **back toward the equilibrium position** (a restoring acceleration), opposite to the displacement.
Question
How long does equilibrium → maximum displacement take?
Answer
**T/4** — one quarter of the period (each quarter-cycle takes the same time).
Question
How long does it take to go from one extreme to the other extreme?
Answer
**T/2** — half a period (two quarter-cycles, passing through the centre).
Question
What is the SHM defining condition (given in the data booklet)?
Answer
$a = -\omega^{2}x$ — acceleration proportional to displacement and directed back toward equilibrium.
Question
How is the period T related to angular frequency ω?
Answer
$T = \dfrac{1}{f} = \dfrac{2\pi}{\omega}$ — both given in the data booklet.
Question
Common mistake about where the speed is greatest?
Answer
Thinking it is greatest at the ends — it is greatest at the **centre** and **zero** at the ends.
Question
In one full cycle, how many equal quarter-periods are there, and how long is each?
Answer
**Four** quarter-periods, each lasting **T/4**.
Question
On an x–t graph, where is the velocity zero?
Answer
Where the graph is **flat**: at the peaks and troughs (the turning points).
Question
On an x–t graph, where is the speed greatest?
Answer
Where the graph is **steepest**: as it crosses x = 0 (equilibrium).
Question
Speed of an SHM oscillator at displacement x?
Answer
**v = ±ω√(x₀² − x²)** (given). At x = 0 it is v max = ωx₀.
Question
What does "in phase" mean for two oscillations?
Answer
They **peak at the same time**: no time gap between them.
Question
What does φ do in x = x₀ sin(ωt + φ)?
Answer
It sets **where the cycle starts**: φ = 0 from equilibrium, φ = π/2 from +x₀. In radians.
Read the notes
Full study notes for SHM graphs, phase and timing
Topic 3.1 hub
Simple harmonic motion
More from Topic 3.1
All flashcards in this topic
Physics exam skills
Paper structures & tips
Track your progress with spaced repetition
Sign up free — Aimnova tells you exactly which cards to review and when, so you remember everything before your IB exam.
Start Free