Tuesday, Nov 16, 2010

Went around room and asked students what they told their parents about what they did the last class.

Reviewed all the demos from yesterday. Told students to write them up with the main ideas in their journals.

Demonstrated how sound worked by lining up students. A push on a person at one end caused a push on the next and so on. The pushes were side to side and the disturbance traveled side to side. The person at one end did NOT go to the other end. This kind of wave in which the motion of the particles, in this case people atoms, is side-to-side and the wave travels along in the same direction is called a longitudinal wave. The wave travels a-long the same direction as the motion of the particles. This is how sound travels.

In their notebooks, students sketched the row of people and showed the side to side motion. They labeled this as "longitudinal wave" and wrote down "sound" as an example.

Next the students raised and lowered their arms. This time the motion was up and down but the wave traveled side-to-side. I demonstrated the two directions with my arms. If the arms are at 90 degrees, the two motions are perpendicular. A wave in which the motion of the individual particles (people atoms) is up and down but the wave moves perpendicular to this (side-to-side) is called a transverse wave. An example is light.

Quiz on parts of wave, wavelength-frequency relationship.
Went over quiz on board

Asked if students had tried the Quia activities on waves.

Handed out Lab Sheets for "Show Me A Wave"
Students wrote names on sheets.
I assigned groups of 4 and explained the lab.
Do NOT let go of the slinky or it can get tangled.
Keep the slinky on the ground, NO up and down waves.
Leave enough space so that you do NOT tangle your slinky with others.
If you tangle the slinky and I cannot fix it easily, the cost to you is $10

Show how to generate a standing wave and locate nodes.

In your groups. Two people (slinky holders) will use the slinky, the other two (call and scribe) will take turns calling out a wave which the slinky holders will make. When the called wave has been successfully made, the scribes will check it off on their sheets. The pairs will then switch.

On the back of the lab sheet, sketch the waves for numbers 1, 2, 20 - 23
For 1 - Sketch a transverse wave. Label the peak, trough, wavelength, amplitude
For 2 - Sketch a longitudinal wave. Label the compression, rarefaction, wavelength
Sketch 20-23 and label the nodes and antinodes.

Did lab in hallway. I went around and helped if students had questions.
Most students finished both front and back of the lab sheet. If they didn't finish the back, I asked them to finish it for homework.

Hand out worksheet for Bill Nye Video on Waves
Show Bill Nye Video on Waves didn't quite finish.
Students kept video sheet - will finish tomorrow.

Came back into the classroom. Handed Reading Assignment 11.1. Students are to complete the sheet for homework.

Didn't stamp notebooks.
Towards the end of the period I asked students to write in their notebooks a summary of the day's activities and get the notebooks stamped.

I also reviewed the content objectives and said there might be a quiz next period on the material.
Content objectives:
Student will be able to:
. Longitudinal and transverse waves
. Identify crest, trough, wavelength, compression, rarefaction and correctly associate these with the correct waves.
. Describe the differences between amplitude, wavelength, and frequency
. Explain the relationship between frequency, wavelength, and energy
. Identify nodes and antinodes in a standing wave