Science yr 4 - sound part 1

Sekolah Kebangsaan
Tropicana

Science Year 4

6.1 SOUND

In this lesson, you will learn:
1. Vibration and sound
2. Sound travels
3. Several ways to generate sound.
4. Reflection of sound

.

WTeitahchTeearcAhrefirfaAhrfifah

Sekolah Kebangsaan
Tropicana

6.1.1 Sound and vibration

1. Sound is a type of energy. forth
2. Sound is generated by vibration.

(Vibration – complete back and
motion on material or object)

3. Sound needs a medium to travel through. When a school bell
Sound travel through solid, liquid and air ring, the bell part

medium. vibrating and
Unlike light, sound cannot travel through generating sound

vacuum.
(spaces with no air)

.

Teacher Arfifah

Blowing Sekolah Kebangsaan
when a recorder is Tropicana
blown, the air inside
the recorder vibrates knocking or beating
The wood vibrates
when we knock the
door.

Sound can be
produced in
various ways

Plucking and bowing Clapping
The strings of a guitar When cymbal pieces
vibrates if you pluck it. are clapped together,
they vibrate.

When the objects vibrate,
hence the sound is produced

Teacher Arfifah

6.1.2 Sound travel Sekolah Kebangsaan
Tropicana
Textbook page 114

Sound travels in all directions.

Sound needs medium (solid,
liquid and air) to travels

Teacher Arfifah

Sekolah Kebangsaan
Tropicana

We can hear We can hear
people playing people plucking
piano upstairs guitar in the next

room

This because sound travels through
vibration of materials.

Teacher Arfifah

Sekolah Kebangsaan

6.1.3 Sound can be refleTcrtoepidcana

When waves of sound hit example
hard surface, it is reflected. Speak in empty room,
The reflected sound is call cave, empty hallway
echo.

Direction of reflected sound

Textbook page 16 - 117

Sonar – detect Ultrasound – can
object in water. be heard by
Fishermen use certain animal to
this technology detect their prey
to find school of
hard fish in the sea.
Direction of sound surface

travel

Teacher Arfifah

Vocabulary Sekolah Kebangsaan
generate Tropicana
generated
Meaning
vibration
(getaran) Menghasilkan
dihasilkan
vacuum
complete back and forth
pluck motion on material or
bow object
reflected
echo Spaces with no air
prey (ruang yang tiada udara)

Teacher Arfifah petik

gesek

dipantulkan

gema

mangsa