Physics for IGCSE & O level - Waves And Sounds (Section 2)
1
What wave phenomenon is demonstrated when a wave passes through a narrow opening?
Răspuns
(C)
Diffraction
2
Which of the following are uses of echos in the world?
Răspuns
A
B
C
3
Which of the following are uses of ultrasound?
Răspuns
A
B
C
4
What type of wave is light?
Răspuns
(B)
Transverse
5
What are the repeating patterns in a wave represented by?
Răspuns
(B)
Wavelength
6
The human ear can detect sounds up to a frequency of about:
Răspuns
(B)
20 kHz
7
What can ultrasound be used for in the medical field?
Răspuns
A
C
8
Which type of wave is a sound wave?
Răspuns
(B)
Longitudinal wave
9
Which is a use of ultrasound?
Răspuns
A
B
C
D
10
What does ultrasound help to distinguish?
Răspuns
(B)
Different layers of soft tissue
11
What is an example of the reflection of sound waves?
Răspuns
(B)
An echo
12
What unit is the speed of sound often measured in?
Răspuns
(B)
Meters per second (m/s)
13
Which term describes the maximum displacement of a wave from its rest position?
Răspuns
(B)
Amplitude
14
Which of the following is a characteristic of sound waves?
Răspuns
B
C
D
15
What determines the loudness of a sound?
Răspuns
(C)
Amplitude
16
What is the formula that links speed, frequency and wavelength?
Răspuns
(C)
Speed = Frequency x Wavelength
17
What type of wave is a sound wave?
Răspuns
B
D
18
What does the term 'ultrasound' refer to in terms of frequency?
Răspuns
(C)
Frequencies above 20 kHz
19
Which of the following is an application of the echo-sounding principle?
Răspuns
A
B
C
20
What is ultrasound?
Răspuns
(C)
Sound waves with a frequency above the human hearing range.
21
In the metal testing, what feature of the ultrasound wave changes when it reaches a flaw (tiny gap)?
Răspuns
(A)
Amplitude
22
How is the energy carried by a wave related to its amplitude?
Răspuns
(B)
Energy is proportional to the square of the amplitude.
23
Why is ultrasound used for cleaning delicate machinery?
Răspuns
(B)
It uses vibrations to dislodge dirt.
24
What is one practical application of sonar?
Răspuns
(B)
Measuring the depth of the ocean
25
Which of the following best describes how sound travels?
Răspuns
(B)
Through vibrations of particles in a medium.
26
What is the relationship between wavelength and frequency?
Răspuns
(B)
Inversely proportional
27
Which of the following best describes diffraction?
Răspuns
(A)
The bending of a wave around an obstacle.
28
What is the difference between transverse and longitudinal waves?
Răspuns
A
B
29
How is the pitch of a sound related to the frequency?
Răspuns
(A)
Higher frequency = higher pitch
30
What does the term 'period' represent in the context of waves?
Răspuns
(B)
The time for one complete wave cycle.
31
What does the Doppler effect cause to sound waves when the source is moving toward you?
Răspuns
(B)
Higher frequency, higher pitch
32
Why is ultrasound preferred over X-rays in some medical applications?
Răspuns
(D)
Ultrasound can distinguish between different layers of soft tissue.
33
What happens to the loudness of a sound if the amplitude is increased?
Răspuns
(C)
It increases
34
What is the term for the time it takes for one complete cycle of a wave?
Răspuns
(D)
Period
35
What is a characteristic of a transverse wave?
Răspuns
(B)
The particles of the medium move perpendicular to the wave's direction.
36
In the context of ultrasound, what is the depth of water if the pulse takes 0.1 seconds to travel to the sea-bed and return, and the speed of sound in water is 1400 m/s?
Răspuns
(A)
70 m
37
What happens to the energy of a wave when its amplitude increases?
Răspuns
(B)
The energy increases.
38
What does the amplitude of a sound wave determine?
Răspuns
(B)
The loudness of the sound.
39
Which of the following is NOT listed under 'Waves and sounds'?
Răspuns
(D)
Gravity
40
What are the two main types of mechanical waves?
Răspuns
A
B
41
What type of waves are ultrasound waves?
Răspuns
(C)
Longitudinal
42
Which is an example of wave interference?
Răspuns
(C)
A loud sound from two speakers
43
What happens to the wavelength if the frequency of a sound increases, assuming the speed of sound remains constant?
Răspuns
(B)
It decreases.
44
If a boat uses ultrasound and pulses take 0.02 seconds to travel from the boat to the seabed and back, what is the water depth (assuming the speed of sound is 1400 m/s)?
Răspuns
(B)
14 m
45
If the frequency of a sound wave is 110 Hz and the wavelength is 3 m, what is the speed of the wave?
Răspuns
(C)
330 m/s
46
In metal testing using the echo-sounding principle, what does a flaw (tiny gap) result in?
Răspuns
(B)
Two reflected pulses
47
What is one industrial use of ultrasonic waves?
Răspuns
(D)
All of the above
48
What is the unit for measuring the loudness of sound?
Răspuns
(C)
Decibel (dB)
49
How does increasing the air temperature affect the speed of sound?
Răspuns
(B)
It increases the speed.
50
What term describes the bending of a wave when it passes from one medium to another?
