Physics for IGCSE & O level - Waves And Sounds (Section 3)
1
Why can X-rays not be used for the ultrasound test?
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(A)
Because it can cause cell damage to the fetus
2
Which factor does NOT affect the speed of sound?
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(B)
The frequency of the sound
3
Which of the following statements is true about the relationship between frequency and wavelength?
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(B)
They are inversely proportional.
4
What happens when sound is made louder?
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(C)
The amplitude increases.
5
How many distinct frequencies are the human ear able to recognize?
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(D)
Thousands
6
What is the effect of a change in temperature on the speed of sound?
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(B)
Higher temperature, faster speed.
7
Which factor determines the pitch of a sound?
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(B)
Frequency
8
What are some medical uses of ultrasound?
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A
B
9
What does the speed of sound depend on?
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A
B
10
What affects the speed of sound?
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(C)
The medium it travels through and its temperature
11
What is the value of the frequency for the lower limit of human hearing?
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(A)
20 Hz
12
If a sound wave's frequency is doubled, what happens to its speed (assuming the medium stays the same)?
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(C)
The speed stays the same.
13
What is the name for the bouncing back of a wave when it meets a surface?
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(B)
Reflection
14
If the speed of sound in air is 330 m/s and the frequency is 330 Hz, what is the wavelength?
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(B)
1 m
15
What is an example of a longitudinal wave?
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(C)
Sound waves
16
What type of wave is used in ultrasound imaging?
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(B)
Longitudinal wave
17
Which of these statements about the speed of sound is true?
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(B)
It is faster in solids than in liquids or gases.
18
If a piano note has the same pitch, but is played louder than a guitar note, how does its wave differ?
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(C)
Greater amplitude
19
Which properties of a wave are related to the amount of energy it carries?
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B
A
20
What do we call the number of complete oscillations per second?
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(B)
Frequency
21
What happens when a wave meets a boundary where the medium changes?
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A
B
22
The number of waves per second is called:
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(C)
Frequency
23
What is an example of a transverse wave?
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(B)
Light waves
24
What is the speed of light?
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(B)
3.0 x 10^8 m/s
25
What is an example of a longitudinal wave?
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(C)
Sound waves
26
What happens to the wave if two waves meet with a wave and an identical frequency?
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(C)
Interference
27
If a pulse of ultrasound takes 0.03 seconds to travel from a boat to the sea-bed and return, and the speed of sound in water is 1400 m/s, what is the water depth?
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(A)
21 m
28
What is the meaning of frequency?
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(B)
The number of waves passing a point per second.
29
What unit is frequency measured in?
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(B)
Hertz (Hz)
30
In what medium can sound waves travel?
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A
B
C
31
How can you increase the frequency of a wave?
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(B)
Decrease the wavelength.
32
What does ultrasound refer to?
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(B)
Sound waves with frequencies above the range of human hearing
33
What will happen if the sound is made louder (oscillation on an oscilloscope)?
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(B)
The sound will be louder.
34
What happens to the wavelength when the frequency of a wave increases (assuming the speed is constant)?
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(B)
Wavelength decreases
35
Which of the following is a practical application that uses ultrasound?
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(A)
Measuring the depth of a lake.
36
How is the wavelength of the ultrasound in water calculated, when frequency is 40kHz?
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(A)
Speed of water/40kHz
37
Which characteristic of a sound wave is most closely related to pitch?
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(B)
Frequency
38
How is the speed of a wave calculated?
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(C)
Frequency × Wavelength
39
What causes the Doppler effect?
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(B)
The relative motion between the source of a wave and an observer.
40
What happens to the pitch of a siren as it approaches you?
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(A)
The pitch increases.
41
What is the effect of the Doppler effect?
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(B)
Changing the frequency of a wave due to relative motion.
42
What properties of a wave are directly related to its energy?
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B
A
43
What property of a wave is measured in meters?
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(C)
Wavelength
44
Which of the following is NOT a property of waves?
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(C)
Mass
45
What is the term for the 'echo' effect?
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(A)
Reflection
46
What is the function of the echosounder?
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(B)
To measure the depth of water using sound waves.
47
What causes the 'Doppler Effect'?
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(B)
Relative motion between the source and the observer.
48
What is the unit of frequency?
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(A)
Hertz (Hz)
49
If a sound wave travels from air to water, what happens to its speed?
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(A)
The speed increases.
50
Which of the following is a type of wave that requires a medium?
