SCI.14

SUMMARY

KEY INFORMATION

Students will apply kinematics to understand the factors that affect a car’s stopping distance. They will analyze stopping scenarios and make recommendations to the DC Department of Transportation regarding yellow light timing. Using a 5E instructional model and mathematical modeling, students time lights at actual intersections, take measurements using Google Maps, and create a presentation with their recommendations. Resources include a variety of articles and videos to support instruction with a wide variety of students.

GRADE
HS Physics

TOPIC
Kinematics

LESSONS
Download

DURATION
5-6 Block Periods

INSTRUCTIONAL MODEL
Modeling

AUTHOR(S)
Les Maddox

RESOURCES

The lessons for this Cornerstone require the resources listed below. More information regarding the use of each of the resources can be located in the Cornerstone lesson plans.

TEXTS AND WEBSITES

Video: Stopping Distance Demonstration

Creating a Computational Model

Iona Physics: The Yellow Light Activity

SUPPLIES & TECHNOLOGY

Hot wheels tracks	Construction Paper
Mini race cars	Laptops
Post-it notes	Wood blocks

CURRICULUM INTEGRATION

Cornerstones are relevant, rigorous, and aligned to national learning standards. Use the tabs below to learn more about aligning to standards, embedding the Cornerstone in your unit of study, and preparing to teach the Cornerstones.

STANDARDS
REQUIRED KNOWLEDGE AND EXTENSIONS
PLANNING

STANDARDS

Performance Expectations

HS-PS2-2. Use mathematical representations to support the claim that the total momentum of a system of objects is conserved when there is no net force on the system.

Disciplinary Core Ideas

PS2.A: Forces and Motion

Newton’s second law accurately predicts changes in the motion of macroscopic objects. (HS-PS2-1)
Momentum is defined for a particular frame of reference; it is the mass times the velocity of the object. In any system, total momentum is always conserved. (HS-PS2-2)
If a system interacts with objects outside itself, the total momentum of the system can change; however, any such change is balanced by changes in the momentum of objects outside the system.

REQUIRED KNOWLEDGE AND EXTENSIONS

PRIOR KNOWLEDGE

Students should have prior knowledge of measurements, calculator use and kinematic equations.
Students should already be familiar with the ideas that kinetic energy can be distinguished from the various forms of potential energy. Energy changes to and from each type can be tracked through physical or chemical interactions.
When two objects interact, each one exerts a force on the other, and these forces transfer energy between them.

PLACEMENT

BEFORE

Students should have familiarity with basic kinematic equations, velocity, distance, time, and measurement.

DURING

Use data to support claims involving braking distance, reaction time, yellow light times, and the effects of curves on speed and driving.
Demonstrate knowledge of the physics of driving by making a presentation to a board of driving instructors.

AFTER

Follow this unit with a detailed discussion of momentum and energy relationships.

PLANNING

PLANNING

Newton’s second law accurately predicts changes in the motion of macroscopic objects. (HS-PS2-1)
Momentum is defined for a particular frame of reference; it is the mass times the velocity of the object. In any system, total momentum is always conserved. (HS-PS2-2)
If a system interacts with objects outside itself, the total momentum of the system can change; however, any such change is balanced by changes in the momentum of objects outside the system

INSTRUCTIONAL APPROACH

When delivering inquiry-based instruction, it is critical that the teacher acts as a “facilitator”, providing meaningful feedback and asking critical, probing questions, rather than an “instructor” who delivers information. Teachers should be actively engaged in the Observe-Plan-Instigate process of facilitation in order to help students engage, explore, and make meaning of their learning.

This lesson was developed using the 5E instructional model (Engage, Explore, Explain, Elaborate, Evaluate). While all components may not be implemented on a given day, it is important to give consideration to the overall flow of the content and pacing for students. For example, Day 2 for this lesson would flow as follows:

Explain:
- Stopping Distance article
- Stopping Distance Demonstration Stopping Distance Demonstration (Links to an external site.)Links to an external site.
Explore: Record, Average and Chat Yellow Light Times

The following considerations must be made during the facilitation of the lesson:

The teacher must provide feedback on the process as students move throughout the lesson, and introduce the right learning supports and experiences at the right times to move the learning forward.
The teacher must be present and strategically rotating and observing to gather evidence for feedback.
The observations can provide evidence for feedback in any area, be it academic, social, emotional, or otherwise.
The evidence from observations helps the teacher develop a plan to get to the bottom of a challenge, or launch a new learning approach, or address a growing concern.
It is critical that the teacher acts as an instigator of thought, asking tough questions that fuel students’ innate desire to learn.

BACKGROUND INFORMATION

LESSON PACING

Below is a recommended pacing for this Cornerstone and the objective for each lesson. More information regarding each lesson can be located in the Cornerstone lesson plans.

LESSON	OBJECTIVE
Lesson 1	Suggested Activity: Engage – Fighter Pilot. Suggested Activity: Explore – The Physics of Stopping Distance Lab. Suggested Activity: Explain – The Physics of Stopping Distance Debrief. Homework: Find a traffic light near your commute to the school. In a safe place, find the amount of time it takes for the light to change to red.
Lesson 2	Explain: Stopping Distance Reading Science.Physics.CS1.Lesson2.StoppingDistanceArticle. Explain: Video – Stopping Distance Demonstration. Explore: Record, Average and Chat Yellow Light Times.
Lesson 3	Explain: The Yellow Light – Iona Physics. Open a copy of the document titled “The Yellow Light” here. Elaborate: Lecture / Discussion with Mathematics.
Lesson 4	Elaborate: Lecture / Discussion with Mathematics. Introduce project and students can begin preparing.
Lesson 5	Student Preparation of Presentation.
Lesson 6	Presentations by Students.

District of Columbia Public Schools
1200 First Street NE, 8th Floor
Washington, DC 20002

This content was developed by the teachers
and staff of DC Public Schools.
DCPS.CORNERSTONES@DC.GOV

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.