Waves | OCR A-Level Physics A (H556)

Waves

174 questions
16 subtopics
Module 4: Electrons, waves and photons
Paper 2 and Paper 3

The largest topic on the course: what a progressive wave is, the electromagnetic spectrum, polarisation, refraction and total internal reflection, interference and the double-slit experiment, and stationary waves and harmonics..

It covers progressive waves and their properties, the wave equation, reflection, refraction and diffraction, wave graphs and intensity, the electromagnetic spectrum, polarisation, refraction and refractive index, critical angle and total internal reflection, the principle of superposition, interference, coherence and path difference, two-source interference and Young's double-slit experiment, forming stationary waves, stationary waves on strings and in air columns, measuring the speed of sound, node spacing, amplitude and phase in stationary waves and harmonics and the fundamental mode.

Sample questions from Waves

Answer each one closed book first, then open the answer.

Progressive waves and their properties

What is meant by the amplitude of a wave?

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Amplitude is the maximum displacement of a point on the wave from its equilibrium position.
Reflection, refraction and diffraction

Under what condition do diffraction effects become significant?

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A wave spreads noticeably only when the opening it passes through is about the same size as its wavelength.
The electromagnetic spectrum

In the electromagnetic spectrum, which type of radiation lies between microwaves and visible light?

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Infrared radiation.
Refraction and refractive index

What happens to the direction of a light ray when it passes from a more optically dense medium into a less optically dense medium?

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It bends away from the normal.
The principle of superposition

Describe how interference patterns are created and detected in a microwave superposition experiment.

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A microwave transmitter with a metal reflector or two slits creates interference patterns, which are detected by a microwave probe receiver.
Two-source interference and Young's double-slit experiment

Describe the interference pattern produced in Young's double-slit experiment.

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Monochromatic light passes through two narrow slits and produces an interference pattern of alternating bright and dark fringes on a screen.
Stationary waves on strings and in air columns

Under what condition do stable stationary wave patterns form on a stretched string?

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At resonant frequencies, stable stationary wave patterns form.
Node spacing, amplitude and phase in stationary waves

How does the phase relationship between points differ in progressive and stationary waves?

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In a progressive wave the phase changes continuously along the wave; in a stationary wave all points between adjacent nodes oscillate in phase with each other.

The 16 subtopics

One subtopic is one session. Work down the list.

Subtopic	What it covers	Questions
Progressive waves and their properties	Recall questions on transverse and longitudinal waves, displacement, amplitude, wavelength, period, phase difference, frequency and wave speed, and what a progressive wave transfers.	10
The wave equation	Recall questions on finding period and frequency from an oscilloscope trace, f = 1/T, the wave equation v = fλ and calculations with both.	10
Reflection, refraction and diffraction	Recall questions on defining reflection, refraction and diffraction, when diffraction becomes significant, and demonstrating reflection, refraction and diffraction of water waves in a ripple tank.	8
Wave graphs and intensity	Recall questions on displacement-distance and displacement-time graphs, representing longitudinal waves graphically, and wave intensity: its equation, units, calculation and dependence on amplitude.	9
The electromagnetic spectrum	Recall questions on the structure and speed of electromagnetic waves, the order of the electromagnetic spectrum by frequency, and the typical wavelengths of radio waves, microwaves, infrared, visible light, ultraviolet, X-rays and gamma rays.	18
Polarisation	Recall questions on polarisation and plane polarised waves, why only transverse waves can be polarised, and demonstrating polarisation with polarising filters, crossed polarisers and microwaves with a metal grille.	9
Refraction and refractive index	Recall questions on refraction and refractive index, n = c/v, the direction light bends between media, investigating refraction with rectangular and semi-circular blocks, and Snell's law.	15
Critical angle and total internal reflection	Recall questions on the critical angle, its relationship to refractive index, total internal reflection and the conditions for it, and investigating it with a semi-circular block.	8
The principle of superposition	Recall questions on the principle of superposition, finding a resultant wave graphically, in-phase and antiphase superposition, interference, and the waves used to demonstrate superposition including microwaves.	8
Interference, coherence and path difference	Recall questions on coherence, path difference and phase difference, the conditions for constructive and destructive interference, and why a single light source is used with a double slit.	14
Two-source interference and Young's double-slit experiment	Recall questions on two-source interference with sound, microwaves and light, Young's double-slit experiment and its significance, the equation λ = ax/D, measuring a, x and D, and calculating wavelength.	14
Forming stationary waves	Recall questions on how a stationary wave forms, and on the similarities and differences against a progressive wave.	9
Stationary waves on strings and in air columns	Recall questions on setting up stationary waves on a stretched string and in air columns, boundary conditions, and the node and antinode patterns of the fundamental, second and nth harmonics of a string.	10
Measuring the speed of sound	Recall questions on the techniques used to determine the speed of sound using stationary waves.	9
Node spacing, amplitude and phase in stationary waves	Recall questions on detecting nodes and antinodes, how amplitude and phase differ between stationary and progressive waves, and why adjacent nodes or antinodes are half a wavelength apart.	11
Harmonics and the fundamental mode	Recall questions on the fundamental and the higher harmonics, and on the frequencies at which they occur.	12

Waves is 174 of the 1,862 questions in the guide.Get the guide, £8

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.

Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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.
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.