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