Lesson 7— Loudness, amplitude and oscilloscopes — Original

• Natuurkunde / Scheikunde
• Middelbare school
• havo, vwo
• Leerjaar 2

The properties 

of a wave

This lesson

• The properties of a wave
• An oscilloscope
  
• Amplification

Learning goals

• Describe the three properties of wave
• Know what determines the loudness of a sound
• Explain what an oscilloscope does
• Explain how amplification works

The properties of a wave

A wave

A repeating pattern

How many waves are there in the image below?

How many waves are there in the image below?

A wave has three properties

• Wavelength
  
• Amplitude
  
• Frequency
  

What is meant by...

•  Wavelength
• Amplitude
  
• Frequency

Wavelength

The length of a wave (in cm, m, km)

Amplitude

The distance from the center of the wave to the highest or lowest point (in cm, m, km)

Frequency

The amount of waves per second (in hertz, Hz)

What is the wavelength of this wave?

One block is 2 cm long

What is the wavelength of this wave?

One block is 2 cm long

8 cm

What is the amplitude of this wave?

One block is 2 cm long

What is the amplitude of this wave?

One block is 2 cm long

4,5 cm

What is the frequency of this wave?

1 second

What is the frequency of this wave?

1 second

5 Hz

5 waves/ second

An oscilloscope

Link

Amplification

The Amplitude of a wave...

...Determines the loudness of a sound

Which wave create a louder sound?

Wave 1

Wave 2

Which wave create a louder sound?

Wave 1

Wave 2

Working independently

Do: workbook exercises 5.4

Do: yellow block exercises 5.4

Learning goals

• Describe the three properties of wave
• Know what determines the loudness of a sound
• Explain what an oscilloscope does
• Explain how amplification works

How many waves are there in the image below?

How many waves are there in the image below?

One wave

How many waves are there in the image below?

1b.) How many waves do you count in each of the following three pictures? 

Image 2

Two waves

1c.) How many waves do you count in each of the following three pictures? 

Image 3

1c.) How many waves do you count in each of the following three pictures? 

Image 3

Image 2:

Four waves

2a.)  If one block is 2cm wide, what is the wave length of this wave?

Image 1

2a.)  If one block is 2cm wide, what is the wave length of this wave?

Image 1

Image 2:

16 cm

2b.)  If one block is 2cm wide, what is the wave length of this wave?

Image 2

2b.)  If one block is 2cm wide, what is the wave length of this wave?

Image 2

Image 2:

8 cm

2c.)  If one block is 2cm wide, what is the wave length of this wave?

Image 3

Image 2:

4 cm

3) Which of these two waves has a higher amplitude? Explain.

Image 1

Image 2

3) Which of these two waves has a higher amplitude? Explain.

Image 1

Image 2