4.2 Travelling Waves

Question 1b

Marks: 5

(b)

Match the key word to its correct definition

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[5]

Key Concepts

Question 1c

Marks: 1

The diagram shows a displacement-time graph for an oscillating object.

3b-figure-1

(c)

Determine the time period T for this oscillation

[1]

Key Concepts

Question 1d

Marks: 4

The oscillation shown in part (c) has a wavelength λ of 5 m.

(d)

Calculate:

(i)

The frequency f of the oscillation

[2]

(ii)

The wave speed c

[2]

Key Concepts

Question 2a

Marks: 6

(a)

Complete the following sentences by circling the correct words:

In a transverse / longitudinal wave the oscillations are perpendicular to the direction energy transfer.

In a transverse / longitudinal wave the oscillations are parallel to the direction energy transfer.

Transverse / Longitudinal waves do not require a medium through which to propagate.

A rarefaction is an area of high / low pressure in transverse / longitudinal waves.

Radio waves and the vibrations on a guitar string are examples of transverse / longitudinal waves.

Sound travelling through air is an example of a transverse / longitudinal wave.

[6]

Key Concepts

Question 2b

Marks: 1

The diagram shows a longitudinal wave.

q5a-figure-1

(b)

Mark on the diagram one complete wavelength and label it λ

[1]

Key Concepts

Question 2c

Marks: 6

The diagram shows a longitudinal wave.

file_000-4

(c)

Choose suitable words and phrases to complete the sentences.

Label A indicates a ___________. This is an area of _______ pressure where the particles are ______________________.

Label B indicates a ____________. This is an area of ________ pressure where the particles are __________________.

The particles oscillate __________________________. The direction of motion and energy transfer is _______________________________.

[6]

Key Concepts

Question 2d

Marks: 4

(d)

Draw a line for each statement to identify whether it refers to a displacement-distance graph or a displacement-time graph.

[4]

Key Concepts

Question 3a

Marks: 1

(a)

State the speed of microwaves in a vacuum.

[1]

Key Concepts

Question 3b

Marks: 2

(b)

Calculate the frequency f of an infrared wave with a wavelength λ = 2.5 × 10⁻⁶ m s⁻¹.

[2]

Key Concepts

Question 3c

Marks: 3

(c)

Order the electromagnetic waves by wavelength λ. Write a number from 1 to 7 in the column with 1 being the longest wavelength and 7 being the shortest wavelength.

[3]

Key Concepts

Question 3d

Marks: 2

(d)

State the longest and shortest wavelengths λ for visible light.

[2]

Key Concepts

Question 4a

Marks: 1

(a)

Define a longitudinal wave.

[1]

Key Concepts

Question 4b

Marks: 1

(b)

Define a transverse wave.

[1]

Key Concepts

Question 4c

Marks: 3

(c)

Give three examples of transverse waves.

[3]

Key Concepts

Question 4d

Marks: 1

(d)

State an electromagnetic wave with a frequency higher than visible light.

[1]

Key Concepts

Question 5a

Marks: 2

(a)

State the lowest and highest frequencies that are detectable to the human ear.

[2]

Key Concepts

Question 5b

Marks: 6

(b)

Complete the following sentences by adding the correct words into the gaps:

The frequency of a sound wave is related to its _______. Sounds with a _______ frequency have a high _______. Sounds with a ______ frequency have a low ________.

The amplitude of a sound wave is related to its _______. Sounds with a ________ amplitude have a high _______. Sounds with a _______ amplitude have a low ________.

[6]

Key Concepts

Question 5c

Marks: 4

A fast timer was used to measure the time taken for a sound to travel between two microphones.

4-2-5c-question-stem-sl-sq-easy-phy

The microphones were placed 80 cm apart. The mean time interval was 2.5 ms.

(c)

Calculate the speed of the sound

[4]

Key Concepts

Question 5d

Marks: 3

A signal generator was set to produce a sound wave at 1 kHz. Two microphones detect the sound and show the traces on a double beam oscilloscope.

4-2-5d-question-stem-sl-sq-easy-phy

The second microphone was moved away from the first microphone until the oscilloscope traces aligned. The distance between the microphones at this point showed that the wavelength of the sound wave was 3.4 cm.

(d)

Calculate the speed of the sound

[3]

Key Concepts