Physics for IGCSE & O level - Waves And Sounds (Section 5)
1
If ultrasound pulses take 0.03 s to travel from the boat to the seabed and return, how deep is the water under the boat, assuming the speed of sound in water is 1400 m/s?
คำตอบ
(A)
21 m
2
In metal testing, what does the flaw look like on an oscilloscope?
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(B)
Two reflected pulses
3
What happens to the frequency when a sound source moves towards you?
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(B)
The frequency increases.
4
Which of these are examples of wave interference?
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A
C
5
If a pulse of ultrasound takes 0.1 s to travel to the sea-bed and return, and the speed of sound in water is 1400 m/s, what is the depth of the water?
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(B)
70 m
6
What is the role of an echo-sounder?
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(D)
All of the above
7
What is the difference between transverse and longitudinal waves?
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(B)
Longitudinal waves are always in the same direction, while transverse waves move perpendicular
8
What is the range of frequencies humans can hear?
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(B)
20 Hz - 20 kHz
9
The speed of sound depends on:
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(C)
The medium it travels through
10
What is the Doppler effect?
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(B)
The change in frequency of a wave due to the motion of the source or observer.
11
Which wave effect explains why you can sometimes hear a sound even when you can't see its source?
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(C)
Diffraction
12
What is being refered to when mentioning the 'quality' of a sound?
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(C)
The timbre
13
How are energy and amplitude of a wave related?
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(A)
Energy is proportional to amplitude.
14
How does the amplitude of a sound wave affect the loudness of the sound?
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(C)
Higher amplitude, higher loudness
15
What is the range of human hearing in terms of frequency?
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(B)
20 Hz to 20 kHz
16
What are compressions and rarefactions characteristics of?
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(C)
Longitudinal waves
17
What does the amplitude of a sound wave relate to?
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(D)
The loudness of the sound
18
What is the relationship between the period and frequency of a wave?
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(B)
They are inversely proportional.
19
What is a 'rarefaction' in a sound wave?
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(B)
A region where particles are spread out
20
What type of wave is represented by a Slinky being compressed and then stretched?
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(B)
Longitudinal Wave
21
What is the name of the effect where the observed frequency of a wave changes due to the motion of the source or the observer?
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(D)
Doppler Effect
22
Which of the following is a characteristic of longitudinal waves?
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(B)
They require a medium to travel.
23
What is the unit for measuring the speed of sound?
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(C)
Meters per second
24
What do musical instruments produce?
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(A)
Complex waves
25
In the context of medical applications, why is ultrasound often preferred over X-rays?
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(B)
Ultrasound is safer because X-rays can cause cell damage
26
What are the two main types of waves?
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(C)
Transverse and longitudinal
27
What is an example of a medical use of ultrasound?
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(B)
Breaking kidney stones
28
What is the relationship between the period and the frequency?
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(B)
Inversely Proportional
29
What is the role of the ultrasound transmitter/detector in the womb scanning process?
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(A)
To send ultrasound pulses and receive reflections
30
Which of the following is an example of reflection?
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(B)
An echo
31
Which of these options can be cleaned with ultrasound?
คำตอบ
(D)
All of the above
32
What type of wave is produced by a slinky toy when pushed and pulled?
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(B)
Longitudinal wave
33
How does the wavelength change when the frequency increases, assuming the speed of the wave remains constant?
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(B)
The wavelength decreases.
34
When does refraction of a wave occur?
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(C)
When a wave passes from one medium to another and changes speed
35
What is the relationship between speed, frequency, and wavelength?
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(C)
Speed = Frequency x Wavelength
36
What type of wave does light represent?
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(C)
Transverse wave
37
What happens to the direction of the waves when they encounter a vertical surface?
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(A)
They are reflected
38
How is the period of a wave related to its frequency?
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(B)
Period = 1 / frequency
39
What is the term for the distance between two successive crests or troughs of a wave?
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(C)
Wavelength
40
In which medium do sound waves travel the fastest?
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(D)
Solids
41
In a transverse wave, how do the oscillations move in relation to the direction of travel?
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(C)
Perpendicular
42
What is ultrasound?
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(C)
Sounds above the range of human hearing
43
What type of wave is created when you hit the water with a stick?
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(B)
Transverse waves
44
What happens when a wave passes through a small gap (diffraction)?
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(B)
The wave bends and spreads out.
45
What happens to the waves when they pass into a shallower water area?
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(A)
They change direction
46
What affects the speed of sound?
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A
B
C
47
In the context of waves, what does 'speed' refer to?
