Massachusetts Comprehensive Assessment System
2013, High School Intro Physics
Question 32: OpenResponse 

Reporting Category: Motion and Forces Standard: 1.1  Compare and contrast vector quantities (e.g., displacement, velocity, acceleration, force, and linear momentum) and scalar quantities (e.g., distance, speed, energy, mass, and work).
Standard: 1.2  Distinguish between displacement, distance, velocity, speed, and acceleration. Solve problems involving displacement, distance, velocity, speed, and constant acceleration.

A student leaves school and walks south, arriving home after 18 min. The distance between the school and her home is 1200 m. At home, the student realizes she left a book at school. She walks back, arriving at the school 18 min later. Determine the student’s average speed as she walks home. Show your calculations and include units in your answer.
 Describe the difference between the student’s average velocity walking home and her average velocity walking back to the school.
 Calculate the total distance the student walked. Show your calculations and include units in your answer.
 Determine the final displacement of the student. 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 difference between displacement, distance, velocity, and speed. The response correctly determines the student’s average speed walking home and clearly describes the difference between the student’s average velocity walking home and average velocity walking back to school. The response also correctly calculates the total distance the student walked, and correctly determines the final displacement of the student and clearly explains the answer. 
4 
3 
The response demonstrates a general understanding of the difference between displacement, distance, velocity, and speed. 
2 
The response demonstrates a limited understanding of the difference between displacement, distance, velocity, and speed. 
1 
The response demonstrates a minimal understanding of the difference between displacement, distance, velocity, and speed. 
0 
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: Motion and Forces
 Question 32: Motion and Forces
 Question 44: Heat and Heat Transfer
 Question 45: Waves and Radiation
Return to the MCAS 2013 Student Work Directory
Last Updated: December 11, 2013
