Infrasonic Sound

Q.

Distinguish between infrasonic and ultrasonic.

Q.

One of the following can hear infrasound. This one is

(a) dog

(b) bat

(c) rhinoceros

(d) humans

Q.

Write the audible, infrasonic & ultrasonic frequency range.

Q.

write any two difference between Audible & ultrasonic sound

Q.

Can you hear the sound produced due to vibrations of a seconds' pendulum ? Give reason.

Q.

What type of sound waves are produced by a vibrating simple pendulum ?

Q.

Infrasound can be heard by

1. Dog

2. Bat

3. Rhinoceros

4. Human beings

Q.

How are the moths able to escape from the bats? [2 MARKS]

Q.

Sound with frequency above 20, 000 Hz is called ultrasonics.

1. True
2. False

Q.

(a) What is the difference between infrasonic waves and ultrasonic waves?

(b) Choose the infrasonic waves and ultrasonic waves from the following frequencies :

(i) 10, 000 Hz

(ii) 30, 000 Hz

(iii) 18 Hz

(iv) 50, 000 Hz

(v) 10 Hz

Q.

Ultrasonic waves have frequency

1. below 20 Hz

2. between 20 Hz and 20 kHz

3. only above 20 kHz

4. none

Q. Sound corresponding to which frequency is/are ultrasonic sound?

1. 30Hz
2. 30, 000Hz
3. 3, 000Hz
4. 3, 00, 000Hz

Q.

What makes a low pitch sound?

Q.

Which of the following frequency of sound can be generated by a vibrating simple pendulum as well as by the vibrating vocal cords of a rhinoceros ?

(a) 5 kHz

(b) 25 Hz

(c) 10 Hz

(d) 15, 000 Hz

Q.

A stationary rail engine produces whistle with a frequency 2600 Hz. A person standing at a distance of 550 m from engine will listen ___________ no. of waves within one minute.

1. 156 x 10³

2. 26 x 10⁴

3. 156 x 10⁵

4. 26 x 10⁵

Q. Question 7
Earthquake produces which kind of sound before the main shock wave begins

(a) ultrasound
(b) infrasound
(c) audible sound
(d) none of the above

Q. Question 9
Infrasound can be heard by

(a) dog
(b) bat
(c) rhinoceros
(d) human beings

Q. What type of sound does simple vibrating pendulum create

Q. What is the audible range of frequency?

1. 20 Hz - 2000 Hz
2. 20 Hz - 20000 Hz
3. 200 Hz - 20000 Hz
4. 200 Hz - 200000 Hz

Q. Question 7
Earthquake produces which kind of sound before the main shock wave begins

(a) ultrasound
(b) infrasound
(c) audible sound
(d) none of the above

Q. A sound with frequency is inaudible to human being.

1. 50 Hz
2. 40 kHz
3. 15 kHz

Q. A sound wave of wavelength $25\text{m}$ travels at a speed of $350\text{m/s}$. Is it audible for a human being? Explain.
$\left[3\text{marks}\right]$

Q.

How do some animals possibly know about the earthquakes before human beings? Do bats use the same ability to hunt their prey?
[3 MARKS]

Q.

Which kind of sound is produced in an earthquake before the main shock wave begins ?

(a) ultrasound

(b) infrasound

(c) audible sound

(d) none of the above

Q. ntA tuning fork vibrating with a sonometer, having tension in the wire as T, produces 4 beats per sec. The beat frequency does not change when the tension in the wire changes to 1.21T. Find the frequency of the tuning fork assuming that the sonometer wire is vibrating in the same mode in both of the two cases.n

Q. Name the instrument used in the laboratory to produce sound of a fixed frequency.

Q. Match the frequency range of the sound with its name.

1. 10 Hz
2. 100 Hz
3. 40 kHz

Q. Question 7
Earthquake produces which kind of sound before the main shock wave begins

(a) ultrasound
(b) infrasound
(c) audible sound
(d) none of the above

Q.

Sound waves with frequency less than 20 Hz is called:

1. Infrasonic

2. Supersonic

3. Ultrasonic

4. Sonic boom

Q. Question 16
For hearing the loudest ticking sound heard by the ear, find the angle x in the Figure.