Join
Topic

Sound

Estimated reading: 3 minutes 943 views Contributors
Don't Miss Out! Join Darasa Huru

Get instant educational updates, notes, books, and alerts straight to your phone.

WhatsApp Channel Telegram Channel

Sound: Introduction

– Sound is an important example of a longitudinal wave which is composed of both compressions and rarefactions.
– The frequency range in which compressional disturbances occur is called the sonic spectrum and is very large.
– Compressional waves with frequencies above and below the audio range are called ultrasonic and infrasonic frequencies respectively.

Nature and transmission of sound waves

– Sound waves require a material medium for transmission from one point to another.
– Sound waves therefore cannot be transmitted in a vacuum.
– The rate of transmission diminishes as you move from solids, to liquids then to gases.

Characteristics of Sound Waves

  1. Intensity and loudness – intensity of sound refers to the rate of flow of energy through an area. The loudness of a sound generally varies with the intensity of sound. The frequency of sound waves determines their intensity while the amplitude determines their loudness.
  2. Frequency and pitch – pitch refers to the sharpness of a sound and is determined by its frequency.
  3. Fundamental tones and harmonics – fundamental frequency is the vibration in a wire which has the lowest possible frequency. The fundamental frequency and the tones with the frequencies that are whole multiples of the fundamental are called harmonics. The fundamental frequency is also the first harmonic. The number of segments vibrating in a string depends on the point at which the string is plucked.
Furniture From Wood - Geography Form Two

Quality of Sound or Timbre

– quality of sound can be improved by adding the second harmonic to the fundamental frequency hence the quality depends on the number of harmonics produced simultaneously and their relative intensities.

Furniture From Wood - Geography Form Two

Echo

– Echoes are produced by reflection of sound waves from hard surfaces such as a wall or a cliff.
– To determine the velocity of sound ‘v’ between two successive claps is given as v = distance from the reflecting surface / half the time taken between two successive claps.
Hence; speed ‘v’= distance / time = m/s.

Practice Example 1

A boy strikes a railway line (steel) with a hammer. If the speed of sound in steel is 5,200 m/s, determine the time taken for the sound to reach another boy 2.3 km down the railway line with his ear on the rail.

Solution

Time taken = distance / speed
= 2300 / 5200
= 0.44 seconds.

Factors Affecting the Speed of Sound

a) Temperature – speed increases with increase in temperature especially gases since the change in liquids and solids is small it can be neglected.
b) Nature of transmitting medium – different substances transmit sound waves at various speeds as shown below;

  • Air – 346 m/s
  • Hydrogen – 1339 m/s
  • Water – 1498 m/s
  • Aluminium – 5,000 m/s
  • Iron – 5,200 m/s
  • lass – 4,540 m/s

Practice Example 1

A girl claps her hands once at a distance 250 m from a vertical cliff. If the temperature in the surrounding is 50 C, how long does it take for her to hear the echo?

Read Also:
Solution

Distance travelled = 250 × 2 = 500 m.
Speed of sound = (331.5 m/s at 00) the speed in air increases at about 0.6 m/s per 0°C.
Therefore speed at 50 C = 331.5 + (0.6 × 5) = 334.5 m/s.
Time taken = distance / speed = 500 / 334.5 = 1.5 seconds.

Test Your Knowledge

Click below to generate a short, interactive 5-question quiz based on this lesson.

Don't Miss Out! Join Darasa Huru

Get instant educational updates, notes, books, and alerts straight to your phone.

WhatsApp Channel Telegram Channel
Sound - PreviousWaves INext - SoundFluid Flow

Related articles

No comments yet — be the first to share your thoughts.

Leave a Comment

Share this Doc

Sound

Or copy link

CONTENTS

Made with ❤️ by Darasa Huru

Learning BaseContact

Form One Tour Guiding TIE Book PDF Download (New Syllabus)

Starting out in tourism studies requires more than just memorizing facts about n

Form One Technical Drawing TIE Book PDF (New Syllabus)

In alignment with the updated competency-based curriculum provided by the Tanzan

Form One Solar Power Installation TIE Book PDF (New Syllabus)

In alignment with the updated competency-based curriculum provided by the Tanzan

Form One Refrigeration And Air Conditioning TIE Book PDF Download

In accordance with the latest Tanzania Institute of Education (TIE) competency-b

Form One Plumbing and Pipe Fitting TIE Book PDF Download

Navigating the web for a clean, complete, and uncorrupted copy of the Form One P

Form One Painting And Signwriting TIE Book PDF Download

If you have spent hours scrolling through different educational sites trying to

Form One Ngoma TIE Book PDF Free Download

If you have been trying to track down an authentic and reliable digital copy of

Form One Netball Performance TIE Book PDF

Are you trying to track down a dependable digital copy of the Form One Netball P

Form One Music Performance TIE Book PDF Download

Trying to track down the official Form One Music Performance TIE book PDF? Findi

Form One Music And Sound Technology TIE Book PDF Download

If you are looking for the official Form One Music And Sound Technology TIE book

Form One Motorcycle Mechanics TIE Book PDF Download

Are you looking for the official Form One Motorcycle Mechanics TIE book PDF for

Form One Motor Vehicle Mechanics TIE Book PDF Download

Trying to find the official Form One Motor Vehicle Mechanics TIE book PDF for yo

Chat Icon Close Icon

Subscribe

×
Cancel