Lesson 11 of 14
Objective: Students will demonstrate their understanding of the conservation of momentum by determining the number points to assign on an offending driver's license.
The goal of this lesson is to help students use their understanding of the conservation of momentum and collisions to assign points and identify traffic violations to an at fault driver. This lesson follows a series of lessons where students construct an explanation for momentum and its conservation, apply a problem solving protocol to both momentum and impulse, model the momentum before and after an interaction using graphs and apply their understanding of momentum and its conservation to choose between two eyewitness accounts of a collision and complete a set of challenge problems. This lesson addresses the HSA.REI.A.1 and HS-PS2-2 standards because it asks students to solve for the velocity of a car before and after a collision using their understanding of the conservation of momentum. It aligns with the NGSS Practices of Planning and Carrying Out Investigations (SP3), Analyzing and Interpreting Data (SP4), and Obtaining, Evaluating and Communicating Information (SP8) for Science because students will use their prior knowledge of the conservation of momentum and New York state driving laws to determine whether a driver has enough traffic violations to garner points against his or her license.
Within this lesson, students investigate a crime scene based on an initial crime report. Students discuss ways to find an unknown velocity during an inelastic collision. Students then use their understanding of the conservation of momentum to determine how many points to assign to a driver's license who rear-ends another vehicle. Finally, students complete a free write that correspond to today's lesson. Within this lesson, I ask students to apply their current understanding of momentum to a real-world problem. I assess student understanding throughout the lesson using informal check-ins and assess each student's work at the end of the school day on a scale of 1 (Advanced Beginner) to 5 (Highly Proficient).
This portion of the lesson follows a routine to communicate the ideas that students need to be proficient in by the end of the semester and it also highlights the goals of the lesson to students. I summarize the key ideas through the bell-ringer activity and take attendance while students transfer the projected information into their notebooks. I project a slide with the date, the objective and an additional prompt on the interactive whiteboard with a red label that says "COPY THIS" in the top left-hand corner. Sometimes the additional prompt is a BIG IDEA for the lesson or the Quote of the Day or a Quick Fact from current events that is related to the lesson. The red label helps my students easily interact with the information as soon as they enter the room and avoids losing transition time as students enter the classroom.
Today's additional piece of information is a BIG IDEA which states that the conservation of momentum can be used to determine the final velocities of cars involved in a car crash. Later on in this lesson, I ask students to use the information from an EDpuzzle and a set of websites to determine the number of points to assign to the driver at fault in a car collision. In this lesson, I want students to use their experience successfully working in teams and to gather evidence to build a case that demonstrates a clear understanding of the conservation of momentum for an inelastic collision.
Within this lesson, I include a set of notes in the form of an EDpuzzle that I project at the interactive whiteboard at the front of the room. This part of the lesson focuses on a computational model for the conservation of momentum during an inelastic collision. For the first ten minutes, I play the EDpuzzle at the front of the room for the entire class and pause at the pause points that have I embedded as green question marks in the video. Students write their answers to the pause points in their notebooks.
During the first ten minutes, students take notes in their notebooks. I ask students if they have any questions or concerns about the methods discussed in the video. We have a whole class discussion for 2-4 minutes. Some students ask, "How would we do a similar calculation if the bumper drops off of the smaller vehicle when they collide?" and "How does this work if the accident happens on a dirt road?" During the last minute of this section of the lesson, I post this video on our class Edmodo wall so that students can watch, pause and replay the video outside of class. During the next section, students use information from this example to determine how fast an offending driver travels before and after a collision.
During this portion of the lesson, I ask students to spend 20 minutes or so using understanding of collisions to complete this activity. Students are given the make and model of both cars involved in a car crash. Then, I ask students to spend 25 minutes creating a visual that demonstrates the physics behind the car crash. Students may use this visual component during the June performance based assessment and task (PBAT) process if a student chooses the car collision option instead of the roller coaster option.
1. Backstory: Give the audience the backstory (what’s the significance of the problem)
2. Physics of the Problem (P.o.P.): Give a Quick overview of the problem
3. Solution: Step by Step solution including a description of each step, with equations, units and an actual solution with explanation
4. Framework: Explain the connections between the physical concepts in your solution
5. Tips: Give tips on how to solve similar problems in the future
During this portion of the lesson students use the information from the task I project on the interactive whiteboard at the front of the room, information from the Edmunds' website and an excerpt from the New York state traffic code to act as members of an accident investigation unit while using physics to:
- Determine the total mass of each object
- Determine the speed each vehicle travels before and after the collision
- Determine how many traffic violations occur during the collision and how many points to levy against the offending driver's license according to New York state code
The clip below is an example of student work:
In the next section of the lesson, I ask students to identify the most important and challenging parts of today's lesson in their notebooks.
The closure activity this section asks students to write down ideas about the usefulness of physics to investigating car accidents in their notebooks using a Free Write Routine. A free write is a writing routine where students respond to a guiding question and write for a short period of time, typically between 5 and 10 minutes without regard to a particular structure or grammar. I choose this type of closure instead of a problem or quick check because I want students to demonstrate their current level of understanding of the connections between physics and car accidents in a low pressure activity. Student responses include: "We can estimate how fast a driver was going before and after a crash", "We know how to choose speed limits to make driving safer", and "It looks easier on TV".
This type of closure activity asks students to identify points of weakness in their understanding of the conservation of momentum. To wrap up this section of the lesson, I ask students to share their traffic citations with me by midnight to meet the first deadline.