Thursday and Friday

THURSDAY

You will be showing me your ability to use the properties of fishing line as a musical instrument.  Yeah for you! Your job is to play a piece of music from 8notes.com using at least 5 different notes.  If you do not know how to read music, you may have to go to http://www.harpinanawhinin.com/IMAGES/grand_staff.gif to find out the notes. You can play the music using the virtual keyboard, if you wish.

Grading:   Your musical masterpiece will be graded as follows:

Using at least 5 different strings:  4
Involving all group members:  3
Quality of sound (is it recognizable?):  5
Behavior while other groups are performing :  4

FRIDAY

Today you will be going to PHET to play with a ripple tank, a device to observe waves.  Copy the directions for Activity 1 and Activity 2 into an email window. Email to me at marciarpowell@gmail.com.  Answer in groups of 2-3.  GROUPS larger than 3 people WILL NOT receive points unless I have a note from the substitute teacher.

Activity 1:

A. Water Wave Simulator

First you are going to record your observations about the water wave simulator.

1. What happens to what you see as you move the frequency and amplitude sliders?
2. Now click Show graph and repeat. What do you notice with the graph of the water level? (Use terms like amplitude, crest, trough, wavelength, and frequency)
3. Now rotate your view of the water. Record your observations.
4. What happens if you add a second drip? What happens if you space them close together? Far apart?
5. Turn off the second drip but add a barrier. Record your observations. What happens as you alter the width of the slit?

B. Sound Wave Simulator

Now click on the top tab that says sound.

1. What do you see?
2. What happens when you press the particle button? What happens to the particles as you alter the frequency and amplitude? Record your observations.
3. Click show graph. What happens to the graph as frequency and amplitude are changed?
4. Click on grayscale. What happens when you rotate the view? Record your observations.
5. What happens when you turn the speaker off?
6. Turn the speaker back on after all the particles become still.
7. Turn on the sound. What happens to the sound as you vary the frequency and amplitude?
8. Put the sliders for frequency and amplitude in the middle. What happens if you add a barrier? What if you alter the barrier? What if you add two?

3. Light Wave Simulator

Now click the top tab that says “light”

1. Click “show graph” and “add detector”
2. What happens when you vary the amplitude? What happens if you put the amplitude at 0?
3. What happens to the wavelength and frequency as you change the color?
4. What can you say about the difference in colors?
5. Now add a slit. Move the slit back and forth. What happens as the slit gets closer and farther from the source? Does changing the color affect this?
6. Now set the slit width at 1050 and the barrier location at 2950. Use the target on the detector to compare the amplitudes on each side of the barrier. What happen directly behind the opening versus behind the barrier?
7. Click “Show Screen” and “Intensity Graph.” What do you think these represent and are showing?

Now take the information you have observed using this simulator and write your conclusions. How do you think altering factors like wavelength and frequency affect they way we see and hear? How does this help us understand how things like lenses and walls can alter the way we see certain lights and hear certain sounds?

Activity 2:  

Part I: Determine the speed of waves in water.

1.   Design Your Procedure – What would you do to figure out the speed of waves in water?  Describe the steps you would take and the virtual tools you would use to figure this out.  You should have a clear, step-by-step description that anyone in the class would be able to follow. (No numbers in this section, just a description.)

2.   Collect Your Data – What data did you collect using the procedure you created in #1?  How many times did you collect data to be confident in your accuracy?  The data should be clearly organized in a way that matches your procedure.

3.   Make Your Calculations – What calculations do you need to make on the data you collected?  Show the equations you use and your answer for the speed of waves in water.  Pay attention to significant digits.

4.  Check Your Results – “Doing good science” requires that a researcher’s results can be independently checked by other researchers.  Compare your answer for the speed of waves in water with that of a classmate and record both numbers. 

Why might your numbers be different? 

Should everyone get the same number or is it okay to have different numbers?

What is the percentage difference between your numbers?  Is it “significant”?

Part II: Investigate ripple patterns.

5.   Play With The Ripple Tank – Observe the different ripple patterns you get with changes to the waves and the ripple tank.  For example:

See what happens with one faucet vs two faucets.

Turn the faucets on and off.

Change the frequency and amplitude of the drops.

Add a barrier with one slit or two slits and move the barrier left and right.

Change the width and spacing of the slits in the barrier.