Chapter 10, Lesson 01, "What is Sound?"

Materials:

• Worksheet, 10-01 "What is Sound?"

Objective:

• Students will explain what sound is.
• Students will explain how sound is produced.
• Students will explain how sound energy moves in waves.

Anticipatory Set:* Show students a video on how sound can break a glass. From that explain that sound transfers force from one object to another.

http://www.youtube.com/watch?v=ECNDpCYvaOc

Teacher Input:* Use information at: http://www.physicsclassroom.com/Class/sound/U11L1a.html as a guide.

You hear sounds everyday. You hear snowmachines, bells, and sometimes fire alarms. Sound is a form of energy as we saw in the opening video. It has the ability to break glass and do much more. All sounds are produced by manipulatingair molecules. Here, students at the University of Lancashire are demonstrating how sound manipulates air particles. The air molecules around us are constantly moving. When sound is produced those molecules are squeezed togetherand pulled apart. This rapid movement back and forth is called Vibrating. Define Vibrate: Here we see a guitar string vibrating. The production of sound then creates air with a high concentration of molecules and a low concentration of molecules.

Now lets look at how sound then travels from one place to another. You can think of sound traveling much like this slinky would move if you caused it to vibrate.Show this animation of a wave moving across a slinky. You notice that there are air molecules at different places on the spring and one bumps into another as it moves. If we take away the air molecules the sound would not be able to move and we would not be able to hear it. So, sound has three parts, the first is the creator of the sound. Here is a tuning fork. The tuning fork is started to vibrate here and the wave travels through the air with a series of Compressions and Rarefactions. Then it hits your ear like this. Inside your ear your ear drum (Tympanic Membrane) vibrates the vibrations are sent through a series of bones and then are picked up by the auditory nerve which takes the message to the brain.

Lastly we said that the wave can travel like a spring but the wave also has an amplitude if you measure the pressure as the air moves. We can see this in a special kind of tube here.

http://youtube.com/watch?v=HpovwbPGEoo

If time permits use these two videos to further explain how sound moves.

http://youtube.com/watch?v=HNiojTHQ26c

http://youtube.com/watch?v=Yjz5bcKoogg

Guided Practice:* Students will take turns answering the questions from Page 274.

Independent Practice:* Students will read lesson 1, Pages 272-273 and complete the worksheet "What is Sound?"

Check for Understanding:* Students will take the test on Chapter 10 Lesson 1, "What is Sound?"

Duration:

30 minutes + 10-15 for Independent Practice (Could be longer if taken for homework).

Alaska Content Standards Addressed in this lesson:

• SCI A-1 Students will understand models describing the nature of molecules, atoms, and sub-atomic particles and the relation of the models to the structure and behavior of matter (Structure of Matter);
• SCI A-4 Students will understand observable natural events such as tides, weather, seasons, and moon phases in terms of the structure and motion of the earth (Earth);
• SCI A-6 Students will understand that forces of nature cause different types of motion and describe the relationship between these forces and motion (Motion);
• SCI A-15 Students will use science to understand and describe the local environment (Local Knowledge); and: