Connecting Graphical Representations

6.B Use a model to explain how a force applied to an instrument causes the sound source to vibrate (effect) and make a sound even if we cannot see it.

• All objects vibrate when they make sound.
• A force applied to an object causes that object to vibrate, or move back and forth, which makes a sound.
• A larger force causes more and bigger vibrations and a louder sound.
• A graphical representation of a wave helps us to see the vibrations.
• Within a graphical representation, amplitude is the distance the object moves from its starting point, which is related to the strength of the force applied and the object’s loudness.
• Within a graphical representation, frequency represents how often the sound source moves in a certain amount of time and the pitch we hear in the sound.

Refer to Assessment Key. If students are struggling to use their model to explain how forces applied to an object cause objects to vibrate and make sound, they may need more support before moving into the next lesson set. See the alternate activities that could provide additional opportunities for students to further their learning. Use Rubric for Modeling Motion of an Object Making Sounds to provide feedback to students.

Show the video of the harp player.✱ Show slide G. Tell students that before they get started, they need to watch a video https://youtu.be/XT968ZJeWh0 . They will refer to the video in their answers on the assessment. Show students the video of someone playing a harp. You may want to play the video a couple of times (it’s only a few seconds long).

Ask students to complete the assessment.✱ Have students individually complete Assessment.

Return to the DQB questions. Return to the questions that were identified as those we can now answer and have students individually or in pairs work to answer those questions by attaching the question to a half sheet of paper and then writing the answer below. These can then be placed back up on the DQB.

Ask students to identify questions that they are most interested in pursuing next. Have each student share one such question and allow them to add new questions they have or refine an existing question.