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Question 1:

What is the Doppler effect?

A) The bending of sound waves around obstacles
B) The change in pitch of a sound due to the motion of the source or observer
C) The reflection of sound waves from a surface
D) The interference of sound waves

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Explanation: The correct answer is B) The change in pitch of a sound due to the motion of the source or observer. The Doppler effect is the phenomenon observed when there is relative motion between a sound source and an observer. It causes a change in the frequency and pitch of the sound perceived by the observer. When the source and observer are moving towards each other, the perceived pitch is higher (higher frequency). When they are moving away from each other, the perceived pitch is lower (lower frequency).

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Question 2:

Which of the following factors affects the speed of sound in a medium?

A) Amplitude of the sound wave
B) Frequency of the sound wave
C) Wavelength of the sound wave
D) Properties of the medium, such as density and elasticity

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Explanation: The correct answer is D) Properties of the medium, such as density and elasticity. The speed of sound in a medium depends on the properties of the medium, including its density and elasticity. In general, sound travels faster in denser and more elastic materials. For example, sound travels faster in solids than in liquids, and faster in liquids than in gases.

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Question 3:

How does the brain perceive the loudness of a sound?

A) By the frequency of the sound wave
B) By the amplitude of the sound wave
C) By the wavelength of the sound wave
D) By the speed of sound in the medium

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Explanation: The correct answer is B) By the amplitude of the sound wave. The loudness of a sound is perceived by the brain based on the amplitude of the sound wave. The greater the amplitude of the sound wave, the louder the sound is perceived. Amplitude corresponds to the amount of energy carried by the sound wave, and a higher amplitude wave carries more energy, resulting in a louder sound.

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Question 4:

What is the range of human hearing in terms of frequency?

A) 0 Hz to 10,000 Hz
B) 20 Hz to 20,000 Hz
C) 10 Hz to 100,000 Hz
D) 1 Hz to 1,000 Hz

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Explanation: The correct answer is B) 20 Hz to 20,000 Hz. The range of frequencies that can be heard by the average human ear is approximately 20 Hz to 20,000 Hz. This range may vary slightly among individuals, especially as age can affect the upper limit of hearing. The lowest frequency that can be heard is known as the threshold of hearing, while the highest frequency that can be heard is known as the threshold of pain.

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Question 5:

How does the brain interpret the direction of a sound source?

A) By the frequency of the sound wave
B) By the amplitude of the sound wave
C) By the time delay between the arrival of the sound at each ear
D) By the speed of sound in the medium

Show Answer

Explanation: The correctanswer is C) By the time delay between the arrival of the sound at each ear. The brain perceives the direction of a sound source by comparing the arrival time of the sound at each ear. When a sound source is off-center, the sound reaches one ear slightly before it reaches the other ear. The brain processes this time delay and uses it to determine the direction from which the sound is coming. This mechanism, known as interaural time difference, helps us locate the source of a sound in our environment.