Waves in Matter | OCR GCSE Combined Science Physics, Higher tier (J250)

Waves in Matter

155 questions
12 subtopics
Paper 12 (Physics)
Paper 12 (Physics)

Waves in Matter is examined in Paper 12 (Physics).

It covers amplitude, wavelength, frequency and period, the wave equation, transverse and longitudinal waves, modelling waves with ripples and sound, electromagnetic waves as transverse, and energy transfer, frequency and wavelength across the spectrum, what our eyes detect, and light as an electromagnetic wave, uses of electromagnetic waves, hazards of ultraviolet, X-rays and gamma rays, producing and receiving radio waves, absorption, transmission, refraction and reflection and investigating reflection and refraction of light.

Sample questions from Waves in Matter

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

Amplitude, wavelength, frequency and period

How does the amplitude of a wave relate to the energy it transfers?

Show the answer
A wave of larger amplitude transfers more energy.
The wave equation

Water waves travel at 0.2 m/s with a frequency of 4 Hz. What is their wavelength?

Show the answer
The wavelength is 0.05 m, because 0.2 ÷ 4 = 0.05.
Modelling waves with ripples and sound

Describe how two microphones and a timer can be used to measure the speed of sound in a laboratory.

Show the answer
Place the microphones a measured distance apart in line with the source and record the time between the sound reaching each one, then divide the separation by that time.
Electromagnetic waves as transverse, and energy transfer

Describe the energy transfer when sunlight falls on a solar cell.

Show the answer
Light from the Sun is absorbed by the cell, which transfers the energy to an electrical circuit.
What our eyes detect, and light as an electromagnetic wave

Roughly how much of the whole electromagnetic spectrum can we see?

Show the answer
Only a very small part of it.
Uses of electromagnetic waves

Give two practical uses of gamma rays.

Show the answer
They are used to sterilise surgical instruments and food, and to treat cancer.
Producing and receiving radio waves

How does the frequency of the current induced in an aerial compare with the frequency of the radio wave that produced it?

Show the answer
It is the same as the frequency of the radio wave.
Absorption, transmission, refraction and reflection

In which direction does a ray of light bend when it passes from air into glass at an angle?

Show the answer
It bends towards the normal, because it slows down.

The 12 subtopics

One subtopic is one session. Work down the list.

Subtopic	What it covers	Questions
Amplitude, wavelength, frequency and period	Amplitude, period, wavelength and frequency and their units, the link between period and frequency with calculations, how amplitude relates to energy, how a point in a material moves as a wave passes, and measuring the wavelength of a longitudinal wave.	16
The wave equation	Wave velocity = frequency × wavelength and its units, why a higher frequency means a shorter wavelength at a fixed speed, pitch and wavelength in air, finding velocity from distance and time, and calculations of velocity, frequency and wavelength for sound, water and radio waves.	16
Transverse and longitudinal waves	How the direction of vibration differs in transverse and longitudinal waves, crests and troughs, compressions and rarefactions, an example of each type, and what the two types have in common.	9
Modelling waves with ripples and sound	Why ripples model transverse waves and sound longitudinal ones, methods for measuring the speed of ripples and of sound, and the evidence that waves transfer energy without moving matter along.	16
Electromagnetic waves as transverse, and energy transfer	Electromagnetic waves as transverse waves that cross empty space at about 3 × 10⁸ m/s, why we can see the Sun but not hear it, and how infrared, microwaves, light, radio waves and ultraviolet transfer energy from a source to an absorber, including why a black car heats up faster.	16
Frequency and wavelength across the spectrum	How frequency and wavelength are related for electromagnetic waves, calculations using their common speed, the order of the spectrum, and which colours lie at each end of visible light.	16
What our eyes detect, and light as an electromagnetic wave	The narrow band of visible light the eye detects and the red and violet at its edges, why infrared and ultraviolet cannot be seen and how a thermal camera reveals infrared, and light as a transverse electromagnetic wave with the same speed as microwaves and a colour set by its wavelength.	16
Uses of electromagnetic waves	Practical uses of radio waves, microwaves, infrared, visible light, ultraviolet, X-rays and gamma rays, and why microwaves suit satellite links and light suits optical fibres.	9
Hazards of ultraviolet, X-rays and gamma rays	Effects of too much ultraviolet on skin and how X-rays and gamma rays can harm the body.	9
Producing and receiving radio waves	How oscillating charges in a circuit and aerial produce radio waves, how an arriving wave induces an alternating current of the same frequency, tuning a receiver to one station, the energy transferred on reception, and why radio waves need no material between transmitter and receiver.	8
Absorption, transmission, refraction and reflection	The four things that can happen when a wave meets a substance, examples of absorption varying with wavelength from greenhouses to X-rays, and how and why light refracts entering or leaving glass.	16
Investigating reflection and refraction of light	Investigating reflection by a plane mirror and refraction through a rectangular glass block with a ray box, why a narrow ray and widely spaced crosses give better angles, working safely in a darkened room, the independent and dependent variables, and the spectrum a prism produces.	8

Waves in Matter is 155 of the 1,222 questions in the guide.Get the guide, £7

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.