Advertisements
Advertisements
Question
What is the difference between infrasonic waves and ultrasonic waves ?
Solution
Difference between infrasonic and ultrasonic waves
| Infrasonic waves | Ultrasonic waves |
| These waves have frequencies below 20Hz. | These waves have frequencies above 20 kHz. |
| They are produced by objects vibrating very slowly. | They are produced by objects vibrating very rapidly. |
APPEARS IN
RELATED QUESTIONS
What is the audible range of the average human ear?
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 344 m s−1.
Fill in the blanks with suitable words.
A sound wave consists of places of higher pressure called ................. and places of................pressure called.................
Name the organs of hearing in our body.
What name is given to the sound waves of frequency too high for humans to hear ?
What type of sound waves are produced by a vibrating simple pendulum ?
What are ultrasonic waves ? Name two animals which can produce ultrasonic waves.
Three different vibrating objects produce three-types of sounds X, Y and Z. Sounds X and Y cannot be heard by a man having normal range of hearing but sound Z can be heard easily. The sound X is used in hospitals to break kidney stones of a patient into fine grains which then get flushed out with urine. The sound Y is similar to that which is produced during an earthquake before the main shock wave is generated.
(a) What type of sounds are (i) X (ii) Y, and (iii) Z ?
(b) Name one device which can produce sound like X.
(c) Name one device in a science laboratory which can produce sound like Y.
(d) Name one device in our homes which can produce sound like Z.
(e) What is the frequency range of sounds like Z ?
A girl is sitting in the middle of a park of dimension 12 m × 12 m. On the left side of it, there is a building adjoining the park and on the right side of the park, there is a road adjoining the park. A sound is produced on the road by a cracker. Is it possible for the girl to hear the echo of this sound? Explain your answer.
For hearing the loudest ticking sound heard by the ear, find the angle x in Fig.12.4.
