Perception of Sound

Q.

Two sounds of same loudness and same pitch produced by the two different instruments differ in their:

(a) amplitudes (b) frequencies

(c) wave forms (d) all the above.

Q.

All vibrating bodies produce sound.

1. True
2. False

Q.

Find the minimum and maximum wavelengths of sound in water that is in the audible range $(20—20000Hz)$ for an average human ear. Speed of sound in water$=1450m{s}^{-1}.$

Q.

Two sounds of the same loudness and the same pitch produced by two different instruments differ. Explain and draw diagrams to illustrate your answer.

Q. Question 7
A person has a hearing range from 20 Hz to 20 kHz. What are the typical wavelengths of sound waves in air corresponding to these two frequencies? Take the speed of sound in air as $344m{s}^{-1}$.

Q.

A sound wave travels at a speed of $399m{s}^{-1}$. If its wavelength is $1.5m$, what is the frequency of the wave? Will it be audible?

Q.

How does the two sounds of same loudness and same pitch produced by different instruments differ ? Draw diagrams to illustrate your answer.

Q.

Find the minimum and maximum wavelengths of sound in water that is in the audible range (20 - 20000 Hz) for an average human ear. Speed of sound in water = $1450m{s}^{-}1$

1. 7.25 cm, 72.5 m

2. 100 cm, 1000 m

3. 1 cm, 1 m

4. None of the above

Q. Match the following frequencies with their sound ranges.

1. Audible range
2. Ultrasonic range
3. Infrasonic range

Q.

The quality of sound produced by any two instruments can be the same or different.

1. True
2. False

Q.

Choose the correct option in each of the following:

Which of the following depends on the amplitude of vibrations.

1. Pitch

2. Quality

3. Loudness

4. None of the above.

Q.

Based on the amplitude, what can be determined?

1. Timbre

2. Loudness

3. Frequency

4. Pitch

Q.

The range of infrasonic vibration is in between

Q.

What change do you expect in the characteristics of a musical sound if:

i) its frequency is increased ii) its amplitude is increased

1. i) Pitch will decrease, ii) Loudness will increase

2. i) Pitch will increase, ii) Loudness will increase

3. i) Pitch will increase, ii) Loudness will decrease

4. i) Pitch will decrease, ii) Loudness will decrease

Q.

In the given figure:

Name one characteristic which is the same and another characteristic which is different for the sound produced by the waveforms. Given in the fig (1) and fig (2).

Fig 1 Fig 2

Q.

What is the audible range of sound?

Q. Each of the properties of sound listed in column A primarily depends on one of the quantities in column B. Choose the matching pairs from two columns. Property Quantity

Pitch	Waveform
Quality	Frequency
Loudness	Amplitude

1. Pitch - Waveform
   Quality - Frequency
   Loudness - Amplitude
2. Pitch - Frequency
   Quality - Waveform
   Loudness - Amplitude
3. Pitch - Amplitude
   Quality - Waveform
   Loudness - Frequency
4. Pitch - Waveform
   Quality - Intensity
   Loudness - Frequency

Q.

Quality or timbre of sound is instrumental in distinguishing 2 sounds with

1. Same pitch but different amplitudes

2. Same loudness but different amplitudes

3. Same pitch but different loudness and waveforms

4. Same pitch but different intensities

5. Same pitch and same loudness but different waveforms

Q.

A man $X$ can hear only upto 10 kHz and another man $Y$ upto 20 kHz. A note of frequency 500 Hz is produced before them from a stretched string. Then

1. Both will hear sounds of same pitch but different quality

2. Both will hear sounds of different pitch and different quality

3. Both will hear sounds of different pitch but same quality

4. Both will hear sounds of same pitch and same quality

Q. Bats can perceive ultrasonic waves.

1. True
2. False

Q. The ultrasonic and infrasonic sounds are audible to the human ears.

1. False
2. True

Q. Match the following range of frequencies with their sounds.

1. Infrasound
2. Audible sound
3. Ultrasound