Italicized font represents information to be shared orally or physically completed with the students at this time.

The non-italicized font represents additional information included to support the teacher’s understanding of the content being introduced within the CELL.

ASK WHY

Remind students that sound makes up most of our lives. We use it for safety reasons; like when we step out of a street because of an oncoming car. We use it for enjoyment; like when we listen to music or watch TV. And we use it for communication; like when we tell each other about exciting scientific discoveries!

BRANCH OUT

Remind students that audiologists are ear specialists. Typically, these professionals work with patients who have problems with hearing, balance or other ear-related problems.

GET FOCUSED

Note: This is a succinct response to the Focus Question and is placed here for your reference at this time. A fully developed response to the Focus Question can be found on the PostLab page.

GO DEEPER

As a class, read the Background(s) in the Investigation. Have students read the information aloud or silently to themselves. When students have finished, discuss the following concepts as a class:

• Sounds are generated when any solid, liquid or gas vibrates.
• Vibrations occur when the particles or molecules of matter move repeatedly back and forth. This back and forth movement can be fast or slow depending on the type of matter and the object that is vibrating.
• Vibrations in one object can cause other, neighboring objects to vibrate.
• Since sounds are caused by vibrations, the sounds made by the vibrations can also be transferred from one vibrating object to another.
• Vibrations that cause sound to travel from one object to another in waves are called pressure waves.
• Pressure waves can occur in all types of matter.
• If vibrations occur rapidly, they occur frequently and with a high frequency.
• If vibrations occur slowly, they occur infrequently and with a low frequency.
• The back and forth motion of vibrating matter takes the form of a standing wave.
• The two endpoints of the standing wave are called nodes and the middle point is called an antinode.
• As the vibrations in a standing wave alternate back and forth, pressure is alternately placed on the surrounding air, producing a pressure wave that produces sound.
• The length of the complete standing wave and is called the wavelength.
• The frequency and the wavelength have an inverse relationship. This means that if the frequency is low, then the wavelength is long. If the frequency high, then the wavelength is short.

LEARN THE LabLearner LINGO

The following list includes Key Terms that are introduced in the Investigation Background(s). They should be used, as appropriate, by teachers and students during everyday classroom discourse.

• vibration
• standing wave
• node
• antinode
• pressure wave
• frequency
• wavelength
• pitch

Note: Definitions to these terms can be found on the Introduction page to the CELL.

Note: Additional words may be bolded within the Background(s). These words are not Key Terms and are strictly emphasized for exposure at this time.

SET FOR SUCCESS

• Direct students to complete the Prediction section in their SDRs. Student answers may vary.

• What is sound?
• How can sounds be different from one another?
• How do we detect sounds?

• Explain to students that all matter is able to vibrate and that these vibrations are what cause sound.
• Ask students to place their forefinger and thumb on either side of the front of their throat and hum.
• Ask students what they hear and feel. Students should be able to feel their vocal cords vibrating and hear their humming. Explain to students that the back and forth vibrations of their vocal cords cause the sound that they hear.
• Explain to students that the vibrations of their vocal cords cause the surrounding air to vibrate and that the vibrations of the gas molecules in the air cause their eardrums to vibrate. This allows them to hear the sound of their humming or of any other sound
• Play the video below. Stop to ask students questions or answer students’ questions when necessary. Remind students to follow along with their SDRs and make any notes that they think might be helpful.
• After the video, direct students to divide into their lab groups to discuss their strategy for the lab. For example, they may assign certain group members to perform specific functions during the lab.

Note: The purpose of the video is to allow students to anticipate the laboratory experience they will soon encounter. Students should leave this PreLab session with a firm idea of what to expect and how to perform in the lab.

Note: Homework is posted below the video.

HOMEWORK

Tell students that they should review the Investigation in preparation for the Lab.