What are infrasonic waves? Name two animals which produce infrasonic waves.

Why can’t we hear the sound of squeaks produced by bats?

Name two animals which produce ultrasound.

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

one of the following can hear infrasound. This one is :

A. dog B. bat

C. rhinoceros D. humans

What is kidnapped, blindfolded and imprisoned in a big room. How could the man tell if he was in:

(a) a city (b) a village

(c) a bare room (d) a furnished room?

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 whioch 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?

What are infrasonic waves? Name two animals which produce infrasonic waves.

What are infrasonic waves? Name two animals which can produce ultrasonic waves.

What is sonar? Explain its use.

Which of the following sound frequencies cannot be heard by a human ear?

(i) 10 Hz (ii) 100 Hz

(iii) 10,000 Hz (iv) 15 Hz

(v) 40,000 Hz