# Frank solutions for Class 9 Physics ICSE chapter 7 - Sound [Latest edition]

## Chapter 7: Sound

Production and Propagation of SoundRange of HearingExercise
Production and Propagation of Sound [Page 278]

### Frank solutions for Class 9 Physics ICSE Chapter 7 Sound Production and Propagation of Sound [Page 278]

Production and Propagation of Sound | Q 1 | Page 278

Is sound a form of energy?

Production and Propagation of Sound | Q 2 | Page 278

How is sound produced?

Production and Propagation of Sound | Q 3 | Page 278

Can sound travel through vacuum?

Production and Propagation of Sound | Q 4 | Page 278

Can sound propagate in solids and liquids?

Production and Propagation of Sound | Q 5 | Page 278

Can we produce sound in vacuum?

Production and Propagation of Sound | Q 6 | Page 278

State the main factors on which the speed of sound in a medium depends.

Production and Propagation of Sound | Q 7 | Page 278

What is the approximate value of the speed of sound in air at N.T.P.?

Production and Propagation of Sound | Q 8 | Page 278

Compare approximately the speed of sound in air, water, and iron.

Production and Propagation of Sound | Q 9 | Page 278

In which medium the speed of sound is more: humid air or dry air? Give a reason to your answer.

Production and Propagation of Sound | Q 10 | Page 278

How does the speed of sound depend on (i) Amplitude, and (ii) Wavelength?

Production and Propagation of Sound | Q 11 | Page 278

On placing your ear close to an iron railing which is tapped some distance away, sound is heard twice. Explain, why?

Production and Propagation of Sound | Q 12 | Page 278

What causes sound in air?

Production and Propagation of Sound | Q 13 | Page 278

What is the ratio of speed of light to speed of sound?

Production and Propagation of Sound | Q 14 | Page 278

State the effect of pressure on the speed of sound in air.

Production and Propagation of Sound | Q 15 | Page 278

How does the speed of sound in air vary with the temperature?

Production and Propagation of Sound | Q 16 | Page 278

he sound of an explosion on the surface of a lake is heard by a boatman 120 m away and by a diver 120 m below the point of explosion. Out of the two persons, who would hear the sound first? Why?

Production and Propagation of Sound | Q 17 | Page 278

Describe a simple experiment to determine the speed of sound in air.

Production and Propagation of Sound | Q 18.1 | Page 278

How do the following factor affect the speed of sound in air?
Moisture in air.

Production and Propagation of Sound | Q 18.2 | Page 278

How do the following factor affect the speed of sound in air?
Pressure in air.

Production and Propagation of Sound | Q 18.3 | Page 278

How do the following factor affect the speed of sound in air?
Temperature of air

Production and Propagation of Sound | Q 19 | Page 278

The time interval between a lighting flash and the first sound of thunder was found to be 6 s. If the speed of sound in air is 330 ms-1, find the distance of the flash from the observer.

Production and Propagation of Sound | Q 20 | Page 278

A person fires a gun and other boy at a distance hears the sound of the fire 2.5 s after seeing the flash. If the speed of sound in air is 330 ms-1, find the distance between the boys.

Range of Hearing [Page 284]

### Frank solutions for Class 9 Physics ICSE Chapter 7 Sound Range of Hearing [Page 284]

Range of Hearing | Q 1 | Page 284

What do you mean by the frequency of sound?

Range of Hearing | Q 2 | Page 284

What is the SI unit of frequency?

Range of Hearing | Q 3 | Page 284

Define one hertz.

Range of Hearing | Q 4 | Page 284

What is the audible range of frequency?

Range of Hearing | Q 5.1 | Page 284

Can we hear sounds of frequencies:
Less than 20 Hz

Range of Hearing | Q 5.2 | Page 284

Can we hear sounds of frequencies:
More than 20 KHZ

Range of Hearing | Q 6 | Page 284

Does audible range of frequency vary from person and also with the age of the person?

Range of Hearing | Q 7 | Page 284

What are infrasonic and ultrasonic sounds?

Range of Hearing | Q 8 | Page 284

Is the energy carried by the ultrasound very high or very low?

Range of Hearing | Q 9 | Page 284

State two applications of ultrasound.

Range of Hearing | Q 10 | Page 284

What is echocardiography?

Range of Hearing | Q 11 | Page 284

What does SONAR stand for? Where do we make use of SONAR?

Range of Hearing | Q 12 | Page 284

How are bats able to avoid obstacles in their way?

Range of Hearing | Q 13 | Page 284

What type of sound is produced by elephants and whales?

Range of Hearing | Q 14 | Page 284

Do all animals have same ranges of audible frequencies?

Range of Hearing | Q 15 | Page 284

What do you mean by an echo?

Range of Hearing | Q 16 | Page 284

What is echolocation? How do animals make use of this phenomenon?

Range of Hearing | Q 17 | Page 284

State three important uses of echolocation.

Range of Hearing | Q 18 | Page 284

What are hearing aids?

Range of Hearing | Q 19 | Page 284

State the main components of a hearing aid.

Range of Hearing | Q 20 | Page 284

Describe a simple method to find the depth of a submerged ship.

Range of Hearing | Q 21 | Page 284

State the properties of ultrasound that make it useful.

Range of Hearing | Q 22.1 | Page 284

Name the sound of the frequency given below:

10 Hz

Range of Hearing | Q 22.2 | Page 284

Name the Sound of the Frequency Given Below:
200 Hz

Range of Hearing | Q 22.3 | Page 284

Name the Sound of the Frequency Given Below:
2000 Hz

Range of Hearing | Q 22.4 | Page 284

Name the Sound of the Frequency Given Below:
45 kHz

Exercise [Page 286]

### Frank solutions for Class 9 Physics ICSE Chapter 7 Sound Exercise [Page 286]

Exercise | Q 1 | Page 286

Can you hear each other in a dark room?

Exercise | Q 2 | Page 286

What causes sound?

Exercise | Q 3 | Page 286

Is sound a form of energy?

Exercise | Q 4 | Page 286

Can sound travel through vacuum?

Exercise | Q 5 | Page 286

Does sound require a material medium for transmission?

Exercise | Q 6 | Page 286

Name the factors on which the speed of sound depends.

Exercise | Q 7 | Page 286

What is the effect of wavelength and amplitude on the speed of sound?

Exercise | Q 8 | Page 286

What is the value of sound of room temperature?

Exercise | Q 9 | Page 286

Is the speed of sound different in different media?

Exercise | Q 10 | Page 286

Does the speed of sound in a gas depend on the pressure of the gas?

Exercise | Q 11 | Page 286

Write the formula for speed of sound in a gas using Laplace correction.

Exercise | Q 12 | Page 286

Does the speed of sound depend upon the direction of wind?

Exercise | Q 13 | Page 286

What are ultrasonic?

Exercise | Q 14 | Page 286

What does SONAR stand for?

Exercise | Q 15 | Page 286

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

Exercise | Q 16 | Page 286

Can you hear the sound produced due to the vibrations of second's pendulum?

Exercise | Q 17 | Page 286

Does SONAR make use of infrasonic sound?

Exercise | Q 18 | Page 286

Does ultrasonic in a medium travel faster than the audible sound?

Exercise | Q 19 | Page 286

Exercise | Q 20 | Page 286

What are the requisites of the medium for the propagation of sound? Briefly, explain them.

Exercise | Q 21 | Page 286

What cause sound? Why do we require a material medium for the transmission of sound?

Exercise | Q 22 | Page 286

What is the effect of temperature and pressure on the speed of sound in a gas?

Exercise | Q 23.1 | Page 286

What is the effect of wavelength and amplitude on the speed of sound?

Exercise | Q 23.2 | Page 286

Explain the effect of density on the speed of sound.

Exercise | Q 24 | Page 286

What is sound? Explain with example how does sound travel in a medium.

Exercise | Q 25 | Page 286

Compare approximately the speed of sound in air and steel.

Exercise | Q 26 | Page 286

The smoke from the gun barrel is seen 2 second before the explosion is heard. If the speed of sound in air is 350 ms-1, calculate the distance of observer from the gun.

Exercise | Q 27 | Page 286

Does light travel faster in air than in water? Why?

Exercise | Q 28 | Page 286

Why does the flash of lighting reach earlier than the sound of thunder?

Exercise | Q 29 | Page 286

The sound of which of the following frequency is audible to us?
2 Hz, 1000 Hz, 200 kHz, 8 MHz

Exercise | Q 30 | Page 286

Describe in brief, with the aid of a sketch diagram, an experiment to demonstrate that a material medium is necessary to transmit sound.

Exercise | Q 31 | Page 286

There is no atmosphere on moon. Can you hear each other on the moon's surface?

Exercise | Q 32 | Page 286

State three characteristics of the medium required for the propagation of sound.

Exercise | Q 33 | Page 286

Describe a simple experiment to determine the speed of sound in air.

Exercise | Q 34 | Page 286

What are ultrasonic? State and explain two applications of ultrasounds.

Exercise | Q 35 | Page 286

How are sound waves produced? How are sound waves transmitted from one place to the other?

Exercise | Q 36 | Page 286

Distinguish between light and sound waves. What are the consequences of the large difference in the speed of sound and that of light? Briefly explain them.

Exercise | Q 37.1 | Page 286

How will the following factors affect the speed of sound in air:
Pressure of air.

Exercise | Q 37.2 | Page 286

How will the following factors affect the speed of sound in air:
Temperature of air.

Exercise | Q 37.3 | Page 286

How will the following factors affect the speed of sound in air:
Humidity.

Exercise | Q 37.4 | Page 286

How will the following factors affect the speed of sound in air:
Wind.

Exercise | Q 38.1 | Page 286

Explain how the principle of echo is used by
The bat during its flight at night

Exercise | Q 38.2 | Page 286

Explain how the principle of echo is used by
The dolphin to locate small fish as its prey.

Exercise | Q 39 | Page 286

A person hearing at one end of a long metal bar hears two distinct sounds when the other end is struck with a stone. Explain, giving scientific reasons

## Chapter 7: Sound

Production and Propagation of SoundRange of HearingExercise

## Frank solutions for Class 9 Physics ICSE chapter 7 - Sound

Frank solutions for Class 9 Physics ICSE chapter 7 (Sound) include all questions with solution and detail explanation. This will clear students doubts about any question and improve application skills while preparing for board exams. The detailed, step-by-step solutions will help you understand the concepts better and clear your confusions, if any. Shaalaa.com has the CISCE Class 9 Physics ICSE solutions in a manner that help students grasp basic concepts better and faster.

Further, we at Shaalaa.com provide such solutions so that students can prepare for written exams. Frank textbook solutions can be a core help for self-study and acts as a perfect self-help guidance for students.

Concepts covered in Class 9 Physics ICSE chapter 7 Sound are Production of Sound, Propagation of Sound, Sound Need a Medium to Travel, Characteristics of a Sound Wave, Representation of a Wave, Relationship Between the Wavelength, Wave Velocity and Frequency, Factors Affecting Speed of Sound in Gas, Factors Not Affecting Speed of Sound in a Gas, Experimental Determination of Speed of Sound in Air, Properties of Sounds, Audibility and Range, Speed of Sound in Different Media, Speed of Sound (Velocity of Sound), Sound, Ultrasonic Sound Or Ultrasound, Difference Between the Sound and Light Waves.

Using Frank Class 9 solutions Sound exercise by students are an easy way to prepare for the exams, as they involve solutions arranged chapter-wise also page wise. The questions involved in Frank Solutions are important questions that can be asked in the final exam. Maximum students of CISCE Class 9 prefer Frank Textbook Solutions to score more in exam.

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