Ultrasonic Sound

Q.

Ultrasonic waves are produced by

1. Piezoelectric effect

2. Coulombs law

3. Dopplers effect

4. Peltiers effect

Q.

Define audible, infrasonic, and ultrasonic waves.

Q. As compared to audible sound, ultrasonic waves have:

1. Higher frequency
2. Higher energy
3. Smaller wavelength
4. Higher speed

Q. Sounds of frquency above $20kHz$ is called:

1. Infrasonic sound
2. Supersonic sound
3. Audible sound
4. Ultrasonic sound

Q. What is a shock wave? What is the difference between a sound wave and shock wave?

Q. What is meant by supersonic speed?

Q.

Which instruments work on the basis of reflection of sound waves?

Q.

What name is given to the sound waves of frequency too high for humans to hear ?

Q. Define sound

Q.

What name is given to sound waves of frequencies higher than 20 kHz?

Q.

Electrocardiography is a technique which uses ultrasonic waves to get the image of various parts of the heart.

1. True

2. False

Q.

Complete the following sentences :

(a) An average person can hear sound of frequencies in the range ___ to ___.

(b) Ultrasound is of frequency ___ .

(c) Infrasonic sound is of frequency ___ .

(d) Bats can produce and hear ___ sound.

(e) Elephants produce ___ sound.

Q.

What is ultrasound ?

Q.

Ultrasound has a frequency of vibration

1. between $20$ and $20000\text{Hz}$

2. below $20\text{Hz}$

3. above $20000\text{Hz}$

4. between $500$ and $10000\text{Hz}$

Q. What are infrasonic and ultrasonic sounds ?

Q.

What is the audible range? Name some animals which play games by producing ultrasound.

Q.

Explain the functioning of ultrasonography. [3 MARKS]

Q.

Give various applications of ultrasound.

Q. Pick the devices used for wireless communication.

1. WiFi
2. Data cable
3. Bluetooth
4. HDMI

Q.

Tinku dropped a stone into a very deep well. He hears the sound 6.53 s after he had dropped the stone. Find the depth of the well. Take acceleration due to gravity, g = 10m/s^{​​​​​​2} and Vsound as 340 m/s

Q.

A ship sends out ultrasound that returns from the seabed and is detected after 10 s. If the speed of ultrasound through seawater is 1578 m/s, what is the distance of the seabed from the ship?

Q.

Why are the ultrasonic rays not audible to us?

Q. A sound wave of wavelength $8\text{m}$ travels at a speed of $330\text{m/s}$. Find the type of sound wave.
$\left[2\text{marks}\right]$

Q.

Which of the following statement(s) is/are correct?

1. Ultrasonic sound has a frequency greater than 20 kHz.

2. Ultrasonic sound has a frequency lesser than 20 kHz.

3. Ultrasonic sound carries high energy compared to infrasound of same amplitude.

4. Ultrasonic sound does not bend appreciably at edges of an obstacle because of its small wavelength.

Q.

How is ultrasound used for cleaning?

Q.

Which has the higher frequency - ultrasonic sound or infrasonic sound ?

Q. Fill in the blank.

1. Ultrasound
2. Infrared
3. Acoustic
4. Infrasound

Q. After crossing Sound Barrier will a person be able to hear any sound both from inside and outside

Q. A supersonic plane flies mat the speed

1. less than speed of the sound
2. of the sound
3. greater than sound
4. None of the above

Q. What are ultrasonic waves ?

1. Sound waves having frequency shorter than audio frequency range
2. Sound waves produced in a vaccum
3. Sound waves having frequency higher than audio-frequency range
4. None of these