Oscillations | OCR A-Level Physics A (H556)
Oscillations
- 71 questions
- 5 subtopics
- Module 5: Newtonian world and astrophysics
- Paper 1 and Paper 3
Simple harmonic motion: how it is defined, the relationships between displacement, velocity and acceleration, the interchange of energy, and what happens when an oscillator is damped or driven..
It covers describing simple harmonic motion, the defining equation of simple harmonic motion and timing oscillations, velocity, period and graphical relationships, energy in a simple harmonic oscillator and damping, forced oscillations and resonance.
Sample questions from Oscillations
Answer each one closed book first, then open the answer.
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Describing simple harmonic motion
What does phase difference describe and how can it be expressed?
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The fraction of a cycle between two oscillating quantities, expressed as an angle in radians or degrees. -
Describing simple harmonic motion
Define frequency in the context of oscillations.
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The number of complete oscillations per unit time. -
The defining equation of simple harmonic motion and timing oscillations
How can the period of a mass-spring system be determined experimentally?
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By timing multiple oscillations and dividing by the number of oscillations. -
The defining equation of simple harmonic motion and timing oscillations
Under what initial conditions does the equation x = A sin(ωt) apply to SHM?
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When the oscillator starts at the equilibrium position moving in the positive direction. -
Velocity, period and graphical relationships
At what position does maximum velocity occur in SHM?
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At the equilibrium position where x = 0. -
Velocity, period and graphical relationships
Explain why the gradient of a velocity-time graph gives acceleration for an object undergoing SHM.
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Acceleration is defined as the rate of change of velocity with respect to time (a = dv/dt), so the gradient of a v-t graph at any point directly gives the instantaneous acceleration. -
Energy in a simple harmonic oscillator
What happens to the total mechanical energy of an undamped simple harmonic oscillator during its motion?
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It remains constant throughout the motion. -
Energy in a simple harmonic oscillator
Describe the shape of the potential energy curve on an energy-displacement graph for simple harmonic motion.
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The potential energy curve is a parabola (U-shaped curve).
The 5 subtopics
One subtopic is one session. Work down the list.
| Subtopic | What it covers | Questions |
|---|---|---|
| Describing simple harmonic motion | Recall questions on displacement, amplitude, period, frequency, angular frequency and phase difference for an oscillation, and calculating angular frequency from period or frequency. | 9 |
| The defining equation of simple harmonic motion and timing oscillations | Recall questions on defining simple harmonic motion, a = −ω²x and its negative sign, x = A cos ωt and x = A sin ωt, and measuring the period of a mass-spring system or pendulum using repeat timings and a fiducial marker. | 10 |
| Velocity, period and graphical relationships | Recall questions on velocity and maximum velocity in simple harmonic motion with calculations, isochronous oscillators, gradients of displacement-time and velocity-time graphs, and the phase relationships between displacement, velocity and acceleration. | 16 |
| Energy in a simple harmonic oscillator | Recall questions on the interchange of kinetic and potential energy in simple harmonic motion and the shapes of the kinetic, potential and total energy curves on an energy-displacement graph. | 12 |
| Damping, forced oscillations and resonance | Recall questions on damping and light, heavy and critical damping, free and forced oscillations, natural frequency, resonance and how damping changes the resonance peak, examples of resonance, and investigating forced and damped oscillations. | 24 |
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Nearby topics
OCR A-Level Physics A Active Recall Guide
Every topic, not just this one. 1,862 questions with their answers.