Page 148 - Knowledge Organiser Yr7 24-25

Knowledge Base: Science 7.13 Sound Year 7
2. Sound and Energy Transfer
2.1 Give an example of a longitudinal wave.
2.3 Can sound travel through a vacuum?
2.4 Why does sound travel fastest in a solid?
2.5 Why does light travel faster than sound?
Sound.
No, it needs particles to travel through.
In a solid, the particles are close together.
Light does not rely on particles to transfer vibrations.
4.2 What is the unit for speed?
4.3 What is the unit for distance?
4.4 What is the unit for time?
4.5 How many metres are in one kilometre?
4.6 How many seconds are in one minute?
2.2
How does an object produce sound?
The object vibrates, this causes the air particles around it to vibrate. The air particles bump into each other, transferring the vibrations through the air.
3. Loudness and Pitch
3.1
What two pieces of equipment can we use to see sound?
An oscilloscope and a microphone.
3.2
What does the amplitude of a sound wave show?
The loudness of the sound wave.
3.3
Draw the oscilloscope trace for a loud sound and quiet sound.
3.4
What does the frequency of a sound wave show?
The pitch of the sound wave.
4. Speed of Sound
4.1
What equation can be used to calculate the speed of sound?
speed = distance ÷ time
Metres per second (m/s)
Metres (m)
Seconds (s)
1000m
60 seconds
Worked example question:
Calculate the speed of a sound wave that travels 3400m in 10s.
Calculate the time it takes for sound to travel 1200m.
3.5 What is frequency measured in?
Hertz (Hz)
3.6
Draw the oscilloscope trace for a high and a low pitch sound.
3.7 What is the human auditory range?
20 – 20,000Hz
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