5.4: Loudness, Amplitude and oscilloscopes

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Slide 1: Tekstslide
ScienceMiddelbare schoolvwoLeerjaar 2

In deze les zitten 49 slides, met interactieve quizzen, tekstslides en 2 videos.

time-iconLesduur is: 45 min

Onderdelen in deze les

Slide 1 - Tekstslide

Learning  objectives 
• Name the four properties of a wave (wavelength, amplitude, frequency, speed).
• Describe how the amplitude of a sound wave influences the sound it produces.
• Be able to read waveforms correctly.
• Name the formula for calculating frequency (f = 1/T) and be able to apply it in calculations
• Name the formula for wave speed (v = f x λ) and be able to apply it in calculations.
  

Slide 2 - Tekstslide

Four wave properties
1. Wave length
2. Amplitude
3. Frequency 
4. Speed

Slide 3 - Tekstslide

Slide 4 - Video

Other examples of waves

Slide 5 - Tekstslide

Slide 6 - Tekstslide

Slide 7 - Tekstslide

v=fλ

Slide 8 - Tekstslide

Assignment:
The time that it takes for one complete wave cycle is 0,0025 s. Calculate the frequency and the speed of the wave.
G:  T= 0,0025 s
A:  f=? v=?
 F:  f=1/T
  C: f= 1/0,0025 = 400 Hz



Slide 9 - Tekstslide

Slide 10 - Tekstslide

Slide 11 - Video

DO
Read textbook page 100 and 101
Do questions textbook page 101
Do questions workbook page 48

Slide 12 - Tekstslide

Questions and answers 

Slide 13 - Tekstslide

Slide 14 - Tekstslide

Slide 15 - Link

It takes one soundwave to complete one wave in 0,0025s.
Calculate the frequency

Slide 16 - Open vraag

Open: https://www.szynalski.com/tone-generator/
In the recording a frequency of 500 Hz is used. Using the tone generator: play this tone. If you increase the frequency:
A. What do you hear?
B. What is the maximum frequency you can hear?

Slide 17 - Open vraag

If you decrease the frequency:
A. What do you hear?
B. What is the maximum frequency you can hear?


Slide 18 - Open vraag

Change the seconds/div to 2 ms
A. How much time does it take for 1 wave to complete
B. According to your measurement: what is the frequency?
C. Is this answer different to the previous question?

Slide 19 - Open vraag

Using the information of the previous 2 pages:
A. How much time does it take for 1 wave to complete
B. According to your measurement: what is the frequency?

Slide 20 - Open vraag

Put input to: live input (5V peak amplitude)

Make some noise. Loud and less loud. What happens to the amplitude?

Slide 21 - Open vraag

Using an oscilloscope: how can you see the loudness of a sound

Slide 22 - Open vraag

What can you read from a waveform shown on an oscilloscope

Slide 23 - Open vraag

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

Slide 24 - Tekstslide

1a.)  How many waves do you count in each of the following three pictures? 
Image 1:
One wave.
Image 1

Slide 25 - Tekstslide

1b.) How many waves do you count in each of the following three pictures? 
Image 2

Slide 26 - Tekstslide

1b.) How many waves do you count in each of the following three pictures? 
Image 2
Image 2:
Two waves

Slide 27 - Tekstslide

1c.) How many waves do you count in each of the following three pictures? 
Image 3

Slide 28 - Tekstslide

1c.) How many waves do you count in each of the following three pictures? 
Image 3
Image 2:
Four waves

Slide 29 - Tekstslide

2a.)  If one block is 2cm wide, what is the wave length of this wave?
Image 1

Slide 30 - Tekstslide

2a.)  If one block is 2cm wide, what is the wave length of this wave?
Image 1
Image 2:
16 cm

Slide 31 - Tekstslide

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

Slide 32 - Tekstslide

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

Slide 33 - Tekstslide

2c.)  If one block is 2cm wide, what is the wave length of this wave?
Image 3

Slide 34 - Tekstslide

2c.)  If one block is 2cm wide, what is the wave length of this wave?
Image 3
Image 2:
4 cm

Slide 35 - Tekstslide

3) Which of these two waves has a higher amplitude? Explain.
Image 1
Image 2

Slide 36 - Tekstslide

3) Which of these two waves has a higher amplitude? Explain.
Image 1
Image 2

Slide 37 - Tekstslide

4) Listen to these two sounds. Of which does the sound wave have a higher amplitude?
Sound A
Sound B
  • Make sure to be in presentation mode.
  • Click the icon to play the sound.
  • Make sure to keep the volume of your computer the same!

Slide 38 - Tekstslide

4) Listen to these two sounds. Of which does the sound wave have a higher amplitude?
Sound A
Sound B
  • Make sure to be in presentation mode.
  • Click the icon to play the sound.
  • Make sure to keep the volume of your computer the same!
The soundwaves of sound B have a higher amplitude, because the sound is louder.

Slide 39 - Tekstslide

5) Which of these two sound waves will produce a louder sound? Explain.
Image 1
Image 2

Slide 40 - Tekstslide

5) Which of these two sound waves will produce a louder sound? Explain.
Image 1
Image 2
The soundwaves of imag 2, because they have a higher amplitude.

Slide 41 - Tekstslide

6) Describe what the amplitude of the wave and what the amplitude of a sounds wave says about that sound.

Slide 42 - Tekstslide

6) Describe what the amplitude of the wave and what the amplitude of a sounds wave says about that sound.
The height of the peak of a wave measured from the center.

Slide 43 - Tekstslide

6) Describe what the amplitude of the wave and what the amplitude of a sounds wave says about that sound.
The height of the peak of a wave measured from the center.
The loudness of a sound.

Slide 44 - Tekstslide

6) Describe what the amplitude of the wave and what the amplitude of a sounds wave says about that sound.
The height of the peak of a wave measured from the center.
The maximum displacement of wave compared to it's rest position.
The loudness of a sound.

Slide 45 - Tekstslide

Bonus
1. What do you think happens to the loudness of a sound when two soundwaves meet?

Slide 46 - Tekstslide

Interference

Slide 47 - Tekstslide

Bonus
2. Are sound waves the only form of waves? If not, list other examples of waves. 

Slide 48 - Tekstslide

Bonus
3. Does the medium (for example air, or water) through which a wave moves move with the wave?

Slide 49 - Tekstslide