Analyzing Graphs of

5.A Use mathematical representations of position versus time graphs generated from a tool used to scale up the vibrations of an object to describe wave patterns and support scientific conclusions about how objects move when they make higher-pitch and lower-pitch sounds.

• Look for students to identify amplitude as the distance from at rest to the top of a peak or bottom of a valley.
• Students should calculate frequency as the number of complete vibrations or oscillations in one second.

Students are calculating the amplitude as a review from Lesson 4 but also to show that it is frequency that is changing with the length of the stick and not amplitude. Look for students to notice that the changes in amplitude are the same for both the high-pitch and low-pitch graphs but the frequency of vibrations is more for the high-pitch sound and the short stick. To support students in calculating the amplitude and frequency, refer them to the graphs they annotated in Lesson 4 and to the class definitions on the word wall.