Properties of Waves(Edexcel International A Level Physics)

Expertise

Physics

Properties of Waves

• Waves are generated by oscillating sources
• These oscillations travel away from the source

• Oscillations can propagate through a medium (e.g. air, water) or in a vacuum (i.e. no particles), depending on the wave type

Wave Features

• In order to describe the properties of travelling waves, the following keywords need to be defined:
• Wavelength λ (m) is the distance between a point on a wave and the same point on the next cycle of the wave, e.g. two crests, or two troughs
• Amplitude A (m) is the magnitude of the maximum displacement reached by an oscillation in the wave
• Period T (s) is the time taken for one complete oscillation at one point on the wave
• Frequency f (Hz) is the number of complete wave cycles per second
• Wave speed c (m s-1) is the rate of movement of the wave

Diagram showing the amplitude and wavelength of a transverse wave

• The frequency f and the period T of a travelling wave are related to each other by the equation

Worked example

The graph below shows a travelling wave.

Determine:

(i) The amplitude A of the wave in metres (m)

(ii) The frequency f of the wave in hertz (Hz)

(i) Identify the amplitude A of the wave on the graph

• The amplitude is defined as the maximum displacement from the equilibrium position (x = 0)
• The amplitude must be converted from centimetres (cm) into metres (m)

A = 0.1 m

(ii) Calculate the frequency of the wave

Step 1: Identify the period T of the wave on the graph

• The period is defined as the time taken for one complete oscillation to occur

• The period must be converted from milliseconds (ms) into seconds (s)

T = 1 × 10–3 s

Step 2: Write down the relationship between the frequency f and the period

f =

Step 3: Substitute the value of the period determined in Step 1

f =

f = 1000 Hz

Exam Tip

Every question about waves uses the vocabulary on this page. Many questions start by asking you to define one of them.

So your job is to learn the definitions to the point where you have them memorised.

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The text passage contains a worked example with a mathematical question and its answer, specifically asking to determine the amplitude and frequency of a wave from a graph.
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Properties of Waves(Edexcel International A Level Physics)

Expertise

Physics

Properties of Waves

• Waves are generated by oscillating sources
• These oscillations travel away from the source

• Oscillations can propagate through a medium (e.g. air, water) or in a vacuum (i.e. no particles), depending on the wave type

Wave Features

• In order to describe the properties of travelling waves, the following keywords need to be defined:
• Wavelength λ (m) is the distance between a point on a wave and the same point on the next cycle of the wave, e.g. two crests, or two troughs
• Amplitude A (m) is the magnitude of the maximum displacement reached by an oscillation in the wave
• Period T (s) is the time taken for one complete oscillation at one point on the wave
• Frequency f (Hz) is the number of complete wave cycles per second
• Wave speed c (m s-1) is the rate of movement of the wave

Diagram showing the amplitude and wavelength of a transverse wave

• The frequency f and the period T of a travelling wave are related to each other by the equation

Worked example

The graph below shows a travelling wave.

Determine:

(i) The amplitude A of the wave in metres (m)

(ii) The frequency f of the wave in hertz (Hz)

(i) Identify the amplitude A of the wave on the graph

• The amplitude is defined as the maximum displacement from the equilibrium position (x = 0)
• The amplitude must be converted from centimetres (cm) into metres (m)

A = 0.1 m

(ii) Calculate the frequency of the wave

Step 1: Identify the period T of the wave on the graph

• The period is defined as the time taken for one complete oscillation to occur

• The period must be converted from milliseconds (ms) into seconds (s)

T = 1 × 10–3 s

Step 2: Write down the relationship between the frequency f and the period

f =

Step 3: Substitute the value of the period determined in Step 1

f =

f = 1000 Hz

Exam Tip

Every question about waves uses the vocabulary on this page. Many questions start by asking you to define one of them.

So your job is to learn the definitions to the point where you have them memorised.

Get unlimited access

to absolutely everything:

• Unlimited Revision Notes
• Topic Questions
• Past Papers
user
The text passage contains a worked example with a mathematical question and its answer, specifically asking to determine the amplitude and frequency of a wave from a graph.

TYPE: SINGLE_QUESTION_WITH_ANSWER