Motion of a Toy Car Lab Position vs. Time Graph September 18, 2017 Motion of a Toy Car Lab Position vs. Time Graph

Drill Draw a straight-line diagram of the following situation: Point A is 165 m from Point B. Point B is 193 m from Point C. Point C is 220 m from Point D. Use your diagram to find of the speed of a car when it drives along the following paths: Point A  Point C  Point D  Point B in 3.65 minutes.

Distance vs. Position What do we mean by distance travelled? What about position of an object? Examples: A man starts at the starting line of a race and travels 5.6 m. What distance did he travel? What is his position? A man starts 7.4 meters behind the starting line of a race and travels 5.6 m. What distance did he travel? What is his position? A man starts 6.3 meters in front of the starting line of a race and travels 5.6 m. What distance did he travel? What is his position?

Motion of a Toy Car Lab Today: Gather data Complete data table Homework: Scatterplot, slope, y-intercept, mathematical equation to model your data Data Analysis questions

Motion of a Toy Car Lab Materials: toy car, meter stick, 6 popsicle sticks, stop watch, tape Roles: each group member has a specific role. Procedures: Mark initial position with a post-it. Start the car  timer start time Every five seconds the Timer will say, “Mark!”, and the Driver will place a post-it on the floor next to the toy car. Once all post-its are used, use the meter stick to measure the distance between each popsicle stick and record it in the data table.

Claim-Evidence-Reasoning Conclusion Position vs. Time Graph September 19, 2017 Claim-Evidence-Reasoning Conclusion Position vs. Time Graph

Distance vs. Position What do we mean by distance travelled? What about position of an object? How are they different? Examples: A man starts 7.4 meters behind the starting line of a race and travels 5.6 m. What distance did he travel? What is his position? A man starts 6.3 meters in front of the starting line of a race and travels 5.6 m. What distance did he travel? What is his position?

Drill – Take out Lab Paper A man starts 8.1 meters behind the start line of a race and travels 15.3 m. Then, he turns around and travels 3.6 m back toward the start line. What distance did he travel? What is his final position? A man starts 2.6 meters in front of the start line of a race and travels 8.6 m. Then, he turns around and travels 4.8 m back toward the start line. Then, he turns around a second time and travels 4.7 m. What distance did he travel? What is his final position?

Group Presentation Your group will be presenting your data & analysis from yesterday’s lab on a piece of poster paper. Work Time: 10 minutes Poster Requirements: Position vs. Time graph Mathematical Model (equation) Interpretation of Slope (relationship between variables)

Slope of Position vs. Time Graph What physical quantity has the same unit as the slope of the position vs. time graph?” Slope of a position vs. time graph = speed of the object Position vs. time graphs of fast-moving objects are steeper than that of slow-moving objects. Why??? Graphs do not have to start from the origin – only the slope is important when determining speed.

CERR Conclusion Today: Take 5 minutes to individually complete the Claim-Evidence- Reasoning graphic organizer to plan your conclusion. Two volunteers will share their graphic organizer on the document camera. Homework: Write formal conclusion paragraph – reference rubric Practice worksheet

Position vs. Time Graph Speed, Velocity, Distance, Displacement September 20, 2017 Position vs. Time Graph Speed, Velocity, Distance, Displacement

Drill Get out homework from last night: Position vs. Time Graph worksheet Toy Car Lab Handout Conclusion Graphic Organizer Complete “Interpreting Position vs. Time Graph” worksheet

Position vs. Time Graph Horizontal segment = object is not moving Diagonal segment = object is either moving away from the starting position or moving towards it Positive slope = object is moving away from the start Negative slope = object is moving towards the start Can a position vs. time graph be used for all motion???

Vocabulary Scalar quantity = quantity that tells you only the magnitude Examples: weight, speed, time Vector quantity = quantity that tells you and magnitude and direction. Represented by letter with an arrow over it to signify that the quantity has a direction. Examples: velocity, acceleration Speed = scalar quantity describing how fast something is moving in meters/second (v = d/t)

Vocabulary Average Velocity = vector quantity describing both speed and direction something is moving meters/second v = d/t Distance = scalar quantity that describes how far an object moves in meters Displacement = vector quantity that describes an object’s change in position in meters x = x2 – x1

Velocity Vector quantity describing both speed and direction Rate that position is changing Symbol: v SI units: m/s Relationship: avg velocity = displacement/time vavg = Dx/t

Displacement Vector quantity describing object’s change in position. Concerned with the starting point and ending point of an object, NOT the path taken. Symbol: Dx = x2-x1 Units: meters

Matching Activity Time: 10 minutes Given three sets of cards – 10 Graphs, 10 Scenarios, 10 Data – match the scenario and data that describe each graph. Call me over to check when you are finished. Draw each graph in your notes + write brief description of motion.