The goal of the lesson is for students to see many situations of acceleration and deceleration and to draw multiple representations of motion for each situation including position vs. time graphs, velocity vs. time graphs, acceleration vs. time graphs and motion maps. Students develop models for the situations through graphs and written descriptions from each station of the lab so they can use these to help them understand what is happening to the car's motion in each station. This activity helps students to connect what they see the car doing visually in a situation to graphical representations, diagrammatic representations (motion map) and written descriptions of the motion.
To start out class, I ask students to remind me what they need to do at each station for the Lab Extension Activity. Each station requires students to draw a position vs. time graph, velocity vs. time graph and acceleration vs. time graph based on the data collected and displayed by the motion sensor. They also need to draw the motion map that represents the data and answers a few questions that reference the motion map and graphs. After they have discussed their task for each station, I have them move to the station they left off on from the previous class. Students work with their table groups as they have done in the previous class. I give them 8 minutes at each station and they rotate throughout until they complete all of the stations.
Each station is set up at one table in the back of the room where the motion sensor is attached to the computer. The 7 stations show the following states of motion for the car:
1. Constant velocity in the positive direction
2. Increasing speed in the positive direction
3. Decreasing speed in the positive direction
4. Increasing speed in the negative direction
5. Decreasing speed in the negative direction
6. Up and down the ramp starting in the positive direction
7. Up and down the ramp starting in the negative direction
As the students are working through each station, I walk around and make sure that all of the data on the screens looks accurate and answer questions as they move through the questions at each station. Students are recording data in graphs throughout the activity as well as drawing motion maps and answering questions about the data they collect.
After the students have completed all of the stations, they work on whiteboards to show the position vs. time graph, velocity vs. time graph, acceleration vs. time graph, motion map and written description for one of the stations. Each group signs up for a station by writing the their group number next to the station they are interested in showing, as shown in the picture below. Allowing students to sign up on their own allows them to present the results with which they feel most comfortable.
I give them about 5 minutes to compose their whiteboards and then ask them to set them up on a stand at their tables. As they are working, I check their work to make sure that their graphs and motion maps are accurate. Some student whiteboards are shown below.
When all the groups have finished, I have them go around the room look at each whiteboard and check their own work with each group's board; students have 1 minute at each station. At the end of their carousel, I have students ask any questions they have before they start their homework. I do this activity so that students can check their work and can use this activity as a reference for their homework worksheet.
After students have completed the lab extension stations and the carousel, they have created a reference tool for multiple representations of motion for several situations of uniform accelerated motion (including position vs. time graphs, velocity vs. time graphs, acceleration vs. time graphs, motion maps and written descriptions). My goal for the lab extension activity is to show them a physical example of the motion in addition to how that motion looks on graphs and motion maps. In Worksheet #1 Stacks of Motion Graphs, students are given a position vs. time graph and are asked to complete 4 other representations of motion, similar to what they did in the lab extension activity.
Before the end of class, I go over one of the problems with them to model the process of how I would approach solving the problem. I ask them to choose which one they want me to go over. I show them how I use the lab extension stations as a tool to help solve the problems on the worksheet as in the WS #1 KEY with Questions. I ask students to complete the remaining problems for homework.