Physics for IGCSE & O level - Waves And Sounds (Section 7)
1
If the speed of sound in air is 330 m/s, and a sound has a frequency of 110 Hz, what is its wavelength?
2
What is the range of human hearing?
3
Which of the following could be used to break up kidney stones?
4
Which one of the following is NOT an example of a wave motion?
5
What is the correct formula to calculate speed?
6
What is the formula for calculating the speed of a wave?
Risposta(C)
Speed = Frequency x Wavelength
7
How does ultrasound help in cleaning machinery?
Risposta(B)
By vibrating the machinery
8
What is the name of the effect where waves spread out after passing through a narrow opening?
9
In echo-sounding, what is used to send pulses downwards?
10
How do musical notes of different pitches differ?
11
What type of wave can travel through a vacuum?
12
In the context of sound waves, what are compressions and rarefactions?
Risposta(C)
Regions of high and low pressure.
13
Which two terms best describe the waves that are created on the water surface?
14
What is the relationship between the frequency and the wavelength?
Risposta(B)
By showing that they are inversely proportional.
15
What happens during the reflection of a wave?
16
What will happen to the frequency of a wave if the wavelength doubles (assuming the speed remains constant)?
Risposta(B)
The frequency will halve.
17
What is the approximate upper limit of human hearing?
18
In what medium does sound travel fastest?
19
Which type of wave can be used in medical imaging to examine an unborn baby?
20
Which of the following is an example of a medical use of ultrasound?
21
What is the difference between the trace that will appear on the oscilloscope after a flaw in the metal?
22
Risposta(B)
A region where particles are close together
23
Which of these items can be detected by the use of ultrasound?
24
Which property of a wave determines its pitch?
25
What is the meaning of the word 'amplitude' related to waves?
26
Where do sound waves get their energy from?
27
What is the waves in a ripple tank represents?
28
What happens to the speed of a sound wave as it travels from air to water?
29
If the speed of sound is 330 m/s, and the wavelength is 1 m, what is the frequency?
30
Why is the echo-sounding principle used to detect flaws in metals?
Risposta(B)
To identify tiny gaps in the metal
31
What is the wavelength of the ultrasound if it has a frequency of 20 kHz, and the speed of sound is 1400 m/s in water?
32
What is the speed of sound in air?
33
What happens to the energy of the sound wave when its amplitude increases?
34
In echo-sounding, what is the significance of the time taken for the ultrasound pulse to return?
Risposta(C)
It is directly proportional to the depth of the water.
35
What does 'fundamental frequency' mean?
36
What type of wave travels through a medium?
37
What is the main principle behind metal testing using ultrasound?
38
What does the term 'ultrasonic' mean?
Risposta(B)
Sound waves with a very high frequency
39
What is the relationship between pitch and frequency?
40
Which of these affects the speed of a sound wave?
41
Which of the following correctly describes a transverse wave?
Risposta(B)
The disturbance is perpendicular to the direction of wave travel.
42
What is the speed of sound in water?
43
What is the relationship between the frequency of a wave and its energy?
Risposta(B)
Higher frequency, higher energy
44
What type of wave is created when a stone is dropped into a still pond?
45
What is the frequency of the ultrasound described in the boat echo sounder example if the wavelength is 0.035 m?
46
What are the units for frequency?
47
What is the effect when a wave bends around an obstacle?
48
The speed of sound in water specifically freshwater at room temperature, around 20°C or 68°F is approximately?
49
What is the main application of the 'echo-sounding' principle described?
Risposta(B)
Measuring distance using the time taken for the echo to return
50
What does the amplitude of a sound wave correspond to?
Risposta(A)
The loudness of the sound
