Pre-assessment

Revisit the model from the first day. Feel free to watch the video again if you would like.

What’s traveling between the speaker and the window?

• What is actually moving from the sound source to the window?

• What’s actually traveling between the speaker and the window?

Add to the model below. What would you include in the ? area?

Investigate

How could we use this container (or sealable bag) to help us figure out if air is moving all the way from this sound source to our ears?

1) Place your phone or another speaker inside of a sealed container (tupperware).

2) Dial the phone and let it ring or play music.

3) Record your observations below including a photo and any other important notes about:

Here is a similar video for you two observe.

Is air leaving the container and going to our ears so we can hear it? In other words, is the AIR surrounding the speaker reaching our ears?

Do we need air to hear a sound?

Watch the following video of a phone ringing in a vacuum.

Share your observations below.

Have you ever heard sounds underwater? Describe when this has happened.

Here is a model we have used this year to describe particles of matter. Notice the lines for movement and the spacing of the particles.

Draw a model and share it with your group.

Sound has to have a medium to pass through. Without a medium we would not hear anything.

A medium is matter--such as a liquid, gas or solid--that mechanical waves carry energy through.

Explore

What exactly is traveling across the medium? (If it's not air, what is it?)

Watch the video in the website to better understand what is happening when a sound is produced.

Define

1) longitudinal wave

2) compression

3) rarefraction

4) amplification

5) wavelength

What exactly is traveling across a medium?

What exactly is traveling across the medium?

Use the following website to respond to the questions.

1. You will be working with a single device.

2. Adjust the loudness and pitch so you can see a clear pattern in the particles.

3. Click on a single blue particle to make it red so it is easier to track. Pay attention to the pattern in the whole medium and the motion of this single particle.

How does the wave change as you adjust the loudness and pitch?

As the pitch (or frequency) is increased, the waves per second __________.

As the loudness increases, the size of the force (push or pull) ____________.

What do the particles above represent?

So far we have looked at how particles move and waves that look like squiggles. Below is a diagram to connect the two.