




Massachusetts Comprehensive Assessment System
2017, High School Intro Physics
Question 44: OpenResponse 

Reporting Category: Waves and Radiation Standard: 4.1  Describe the measurable properties of waves (velocity, frequency, wavelength, amplitude, and period) and explain the relationships among them. Recognize examples of simple harmonic motion.

When a child presses a button on a toy car, the car produces a long "beep" sound with a frequency of 500 Hz.
 Calculate the period, T, of the beep. Show your calculations and include units in your answer.
The sound of the beep travels through air at 340 m/s.
 Calculate the wavelength of the beep. Show your calculations and include units in your answer.
The child presses the button and pushes the toy car away. The car moves 5 m before it stops. It continues to beep, even after it stops moving.
 Describe what happens to the amplitude of the beep observed by the child as the car moves away from the child.
 When does the child hear a beep with a frequency lower than 500 Hz? Explain your answer.

Scoring Guide and Sample Student Work Select a score point in the table below to view the sample student response.
Score  Description 
4 
The response demonstrates a thorough understanding of the properties of waves and the Doppler effect. The response correctly calculates the period and the wavelength of the sound. The response clearly describes how the amplitude is observed by the child as the toy car moves away. The response also clearly describes and explains when the child hears a beep with a frequency lower than 500 Hz. 
4 
3 
The response demonstrates a general understanding of the properties of waves and the Doppler effect. 
2 
The response demonstrates a limited understanding of the properties of waves and the Doppler effect. 
1 
The response demonstrates a minimal understanding of the properties of waves and the Doppler effect. 
0 
The response is incorrect or contains some correct work that is irrelevant to the skill or concept being measured. 
Note: There are 2 sample student responses for Score Point 4.
High School Intro Physics
 Question 12: Electromagnetism
 Question 23: Heat and Heat Transfer
 Question 32: Motion and Forces
 Question 44: Waves and Radiation
 Question 45: Motion and Forces
Return to the MCAS 2017 Student Work Directory
Last Updated: September 30, 2018


