3. How sound waves are produced ?
When objects vibrate they produce sound
The vibrations create disturbances which pass through air
as Sound Waves
The waves are carried out by particles (molecules of
gases in air) passing the vibrations along from one
particle to another nearby particle
Each particle in air vibrate back and forth as the sound
wave passes
4. Nature of Sound Waves
Sound Waves are Mechanical Waves
As they need a medium to pass(travel) through and
they can not travel through vacuum ( empty space)
Sound Waves can not travel through vacuum because
there is no particles to pass the energy through
5. Echo
When sound waves reaches a boundary like a
wall it can reflect
Direction of echo
Direction of sound
6. Is a sound that is repeated because the
sound waves are reflected back
Sound waves can bounce off smooth
and hard objects in the same way as a
rubber ball bounces off the ground
Echo
7. Most of music that we hear is now
produced by loudspeakers in Radios or
Headphones
Transform electrical signals into sound
waves
Loudspeakers
8. Musical instruments
Musical instruments create sounds by
making their parts vibrate
Example : Guitars make sound when their
string vibrate
Different Parts of instruments vibrate when
they are hit , blown ,plucked or strummed
9. Musical instruments
Q- Place each of the following musical instruments into one of
three groups –hit ,plucked and blown- depending on the way in
which they produce sound
1- Trumpet
blown
10. Musical instruments
Q- Place each of the following musical instruments into one of
three groups –hit ,plucked and blown- depending on the way in
which they produce sound
2- Piano
plucked
11. Musical instruments
Q- Place each of the following musical instruments into one of
three groups –hit ,plucked and blown- depending on the way in
which they produce sound
3- Recorder
blown
12. Musical instruments
Q- Place each of the following musical instruments into one of
three groups –hit ,plucked and blown- depending on the way in
which they produce sound
4- Guitar
plucked
13. Musical instruments
Q- Place each of the following musical instruments into one of
three groups –hit ,plucked and blown- depending on the way in
which they produce sound
5- Cello
plucked
14. Musical instruments
Q- Place each of the following musical instruments into one of
three groups –hit ,plucked and blown- depending on the way in
which they produce sound
5- Drum
hit
15. Musical instruments
Q- Place each of the following musical instruments into one of
three groups –hit ,plucked and blown- depending on the way in
which they produce sound
6- Saxophone
blown
16. Musical instruments
Q- Place each of the following musical instruments into one of
three groups –hit ,plucked and blown- depending on the way in
which they produce sound
7- Mandolin
plucked
17. Musical instruments
Q- Place each of the following musical instruments into one of
three groups –hit ,plucked and blown- depending on the way in
which they produce sound
7- Harmonica
blown
