Sound
Very Short Answer Type Questions (One Mark Each)
Q.1. Can sound travel through vacuum ?
Answer
Answer: No, sound cannot travel through vacuum.Q.2. What is the nature of sound waves ?
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Answer: Sound waves are longitudinal mechanical waves.Q.3. In which direction medium particles, oscillates in a longitudinal wave ?
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Answer: Parallel to the directions of wave motion.Q.4. What is a transverse wave ?
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Answer: A wave in which medium particles are oscillating along a direction perpendicular to the direction of wave motion.Q.5. Define frequency of a wave?
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Answer: The number of oscillation made by a medium particle in one second is called the frequency of wave.Q.6. Give a relation correlating sound velocity with its frequency and wavelength ?
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Answer: Velocity of sound (v) = frequency (f) x wavelength (λ)Q.7. A sound travels in air with a speed of 330 m/s. Find the wavelength of sound wave if its frequency is 500 Hz.
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Answer: Wavelength (λ) = Velocity of sound (v) / frequency (f) = 330/500 = 0.66 mQ.8. What is SI unit of frequency ?
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Answer: A hertz (Hz), where 1 Hz = 1 oscillation per second.Q.9. What is the true meaning of amplitude of a longitudinal wave ?
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Answer: Maximum variation of pressure (or density) in the given longitudinal wave.Q.10. How is the frequency of a wave related to its time period ?
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Answer: Frequency = 1 / Time periodQ.11. Name the three characteristics of a sound.
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Answer: (i) pitch (ii) Loudness, and (iii) QualityQ.12. On which physical quantity does pitch of a sound depend ?
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Answer: Pitch solely depends on the frequency of sound.Q.13. In an orchestra different musical instruments produce their own sounds. Do these sounds reach us with same speed or different speed ? Why ?
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Answer: With same speed because speed of sound in a medium is same for sounds of all frequencies.Q.14. On what factors does the loudness of a sound depend?
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Answer: Loudness of a sound mainly depends on its amplitude and the response of the listener’s ear to the sound.Q.15. Which sound has higher energy, a loud sound or a soft sound ?
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Answer: A loud sound has more energy associated with it.Q.16. What is the meaning of the characteristic ‘quality’ of a sound ?
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Answer: Quality is that characteristics which enables us to distinguish two different sounds although they may be having same pitch and same loudness.Q.17. On what factors does speed of sound in a medium depend ?
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Answer: Speed of sound in a medium depends on density and elasticity of the medium.Q.18. How does speed of sound in a medium vary on changing the temperature ?
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Answer: Speed of sound in a medium increases with increase in temperature.Q.19. How does speed of sound change when we go from solid to gaseous state ?
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Answer: The speed of sound decreases when we go from solid to gaseous state.Q.20. What is supersonic speed ?