17.2 A2 Level

Energy in simple harmonic motion

Cambridge A-Level Physics (9702)  · Unit 17: Oscillations  · 7 flashcards

Energy in simple harmonic motion is topic 17.2 in the Cambridge A-Level Physics (9702) syllabus , positioned in Unit 17 — Oscillations , alongside Simple harmonic oscillations and Damped and forced oscillations, resonance.  In one line: At maximum displacement, all the energy is stored as potential energy (PE) in the spring, specifically elastic potential energy.

Marked as A2 Level: examined at A Level in Paper 4 (A Level Structured Questions) and Paper 5 (Planning, Analysis and Evaluation). It is not tested on the AS-only papers (Papers 1, 2 and 3).

The deck below contains 7 flashcards — 2 definitions, 4 key concepts and 1 calculation — covering the precise wording mark schemes reward.  Use the 2 definition cards to lock down command-word answers (define, state), then move on to the concept and calculation cards to handle explain, describe, calculate and compare questions.

Key definition

What form of energy does a mass-spring system have at its maximum displacement during SHM

At maximum displacement, all the energy is stored as potential energy (PE) in the spring, specifically elastic potential energy.

What the Cambridge 9702 syllabus says

Official 2025-2027 spec · A2 Level

These are the exact learning outcomes Cambridge sets for this topic. The candidate is expected to be able to do each of these on the relevant paper.

  1. describe the interchange between kinetic and potential energy during simple harmonic motion
  2. recall and use E = 2
  3. for the total energy of a system undergoing simple harmonic motion

Cambridge syllabus keywords to use in your answers

These are the official Cambridge 9702 terms tagged to this section. Mark schemes credit responses that use the exact term — weave them into your answers verbatim rather than paraphrasing.

kinetic energy potential energy total energy

Tips to avoid common mistakes in Energy in simple harmonic motion

Key Concept Flip

Describe the energy transformation that occurs during simple harmonic motion (SHM).

Answer Flip

In SHM, there is a continuous interchange between kinetic energy (KE) and potential energy (PE). At maximum displacement, all energy is PE; at equilibrium, all energy is KE.

Definition Flip

What form of energy does a mass-spring system have at its maximum displacement during SHM?

Answer Flip

At maximum displacement, all the energy is stored as potential energy (PE) in the spring, specifically elastic potential energy.

Definition Flip

State the equation for the total energy (E) of a system undergoing simple harmonic motion.

Answer Flip

The total energy of a system undergoing SHM is given by: E = (1/2) * m * ω² * A², where m is the mass, ω is the angular frequency, and A is the amplitude.

Key Concept Flip

How does the total energy of a SHM system change if the amplitude is doubled, assuming all other factors remain constant?

Answer Flip

If the amplitude (A) is doubled, the total energy (E) increases by a factor of four, since E is proportional to A². Thus, the new energy E' = 4E.

Calculation Flip

A mass-spring system undergoing SHM has a total energy of 4J and an angular frequency of 2 rad/s. If the mass is 0.5 kg, what is the amplitude of the motion?

Answer Flip

Using E = (1/2) * m * ω² * A², rearrange for A: A = √(2E / (mω²)). Substituting values: A = √(2 * 4 / (0.5 * 2²)) = √4 = 2 m.

Key Concept Flip

How is kinetic energy related to velocity during SHM?

Answer Flip

Kinetic energy (KE) is maximum at the equilibrium position where velocity is maximum, and minimum (zero) at the extreme positions where velocity is zero. KE = (1/2)mv²

Key Concept Flip

Explain how potential energy changes as an object moves from the equilibrium position to its maximum displacement in SHM.

Answer Flip

As an object moves from the equilibrium position to maximum displacement, its potential energy increases, while its kinetic energy decreases. At maximum displacement, all energy is potential energy.

Review the material

Read full revision notes on Energy in simple harmonic motion — definitions, equations, common mistakes, and exam tips.

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More Physics flashcards

Browse every 9702 flashcard topic by syllabus area.

All Physics Flashcards
17.1 Simple harmonic oscillations 17.3 Damped and forced oscillations, resonance

More topics in Unit 17 — Oscillations

Energy in simple harmonic motion sits alongside these A-Level Physics decks in the same syllabus unit. Each uses the same spaced-repetition system, so progress in one informs the next.

Key terms covered in this Energy in simple harmonic motion deck

Every term below is defined in the flashcards above. Use the list as a quick recall test before your exam — if you can't define one of these in your own words, flip back to that card.

What form of energy does a mass-spring system have at its maximum displacement during SHM
Equation for the total energy (E) of a system undergoing simple harmonic motion

How to study this Energy in simple harmonic motion deck

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