Animals making sounds
Developing: Describe how sound travels from one place to another.
Secure: Explain the differences between sounds.
Excelling: Analyse how animals use sound in different ways.
Entrance Activity
Discuss in pairs how does a lion roar?
Key words
amplitude
frequency
hertz (Hz)
intensity
pitch
vibrate
vocal folds
volume
What is sound?
Sound is when particles of a
medium (like air or
water)vibrate and squash
together (compression) and
spread out (rarefaction).
There is no sound in space
because there are no particles!
Not all sounds are the same.
They can have different
intensities, amplitudes,
frequencies and pitches.
Draw the particle diagram of how sound travels through a medium.
Animals making sounds
Developing: Describe how sound travels from one place to another.
Secure: Explain the differences between sounds.
Excelling: Analyse how animals use sound in different ways.
Entrance Activity
Discuss in pairs how does a lion roar?
Key words
amplitude
frequency
hertz (Hz)
intensity
pitch
vibrate
vocal folds
volume
Different types of sounds?
Some sounds are loud and some are soft. This is the intensity
of the sound. Sounds with a high intensity are often said to
have a high volume.
Sounds can also be high or low. This is the pitch of the sound.
The pitch and volume of the sound depend on the way an
object vibrates to make the sound.
Smaller objects vibrate faster and make notes with higher
pitches. The number of vibrations each second is called the
frequency. The units for frequency are hertz (Hz). A bell that
vibrates 400 times per second has a frequency of 400 Hz.
Different types of sounds?
The volume of a note depends on the size of the vibrations.
The size of a vibration is its amplitude. The bigger the
amplitude, the louder the note.
Draw this amplitude diagram
in your notes!
How old are your ears?
1) What has a higher pitch a screaming girl or a bear growling? (1 marks)
2) What changes the pitch of a sound? (1 mark)
3) How does sound travel from one place to another? (2 marks)
4) How else can we say sounds are a high or low intensity? (2 marks)
5) Write a definition for frequency (1 mark)
6) A tuning fork vibrates 500 times per second. (2marks)
a. What is its frequency?
b. How will it sound different to a tuning fork that vibrates 300 times per second?
Animals making sounds
Developing: Describe how sound travels from one place to another.
Secure: Explain the differences between sounds.
Excelling: Analyse how animals use sound in different ways.
Entrance Activity
Discuss in pairs how does a lion roar?
Key words
amplitude
frequency
hertz (Hz)
intensity
pitch
vibrate
vocal folds
volume
Why do we make noise?
In pairs discuss
why humans
make noise.
Write down different ways that animals use
sound.
Vocal folds
Humans make sound using two flaps called vocal folds across our
windpipes. These can vibrate when air moves across them. Most
animals make noises in a similar way. But there are other ways to
make noise…
Animal sounds
Male grasshoppers chirp by rubbing one leg against a
wing. Their hind legs have teeth on them and when these
scrape against a wing it makes a sound. (like scraping a
stick along a fence)
Animals can make noise by hitting things. Male
gorillas thump their chests or thump the ground
to threaten other males.
Plenary
Complete questions below.
1. A giant hummingbird flaps its wings about 12 times per second and bee
hummingbirds can flap at over 80 times per second. Explain how the noise made by the
wings of each species will sound different.
2. Two male gorillas are beating their chests.
a. One makes a lower sound than the other. Suggest what this could tell you about the
two gorillas. Explain your answer.
b. Explain how one of them could make a louder sound than the other.
3. Henna says: “Large animals always make lower sounds than small animals.” Explain
how you could find out if she is right.
Animals making sounds
Developing: Describe how sound travels from one place to another.
Secure: Explain the differences between sounds.
Excelling: Analyse how animals use sound in different ways.
Entrance Activity
Discuss in pairs how does a lion roar?
Key words
amplitude
frequency
hertz (Hz)
intensity
pitch
vibrate
vocal folds
volume