Bell Ringer 9/6 The following data is distance and time measurements from a buggy. Calculate the Average time for each distance. Distance (m) Time (s) Trial 1 Trial 2 Trial 3 Average 0.5 1.1 1.3 1.0 1.9 2.1 2.2 1.5 2.6 2.4 2.7 2.0 3.2 3.3 3.5

Bell Ringer 9/7 1. A basketball player catches the ball and begins to run. He travels 8 meters due west, he then turns around and travels 8 meters east. Finally, he travels 2 meters west. a. What is the basketball player’s total distance? b. What is the basketball player’s displacement?

Conclusion Describe the motion of the buggy using SPEED using the words distance and time. Calculate the speed = distance time Describe the Velicity of the buggy using the terms displacement and time. Describe in words what the slope of the line on the graph means. 5. Sources of Error

1. What device on your car keeps it at a constant speed? Bellwork 1. What device on your car keeps it at a constant speed? 2. Is this the same as traveling at a constant velocity?? The cruise control feature!

Bell Ringer 2. What does the slope of the following graphs tell us about the car’s motion? Distance (m) Time (s) Distance vs. Time Time (s) Displacement (m) Displacement vs. Time

Slope of graph tells us…… Speed and Velocity Constant speed Same distance in same time Constant velocity Same speed in same DIRECTION Distance (m) Time (s) Distance vs. Time Time (s) Displacement (m) Displacement vs. Time Constant motion: same distance in the same amount of time (CONSTANT SPEED), in the same direction (CONSTANT VELOCITY)

Speed vs. Velocity Speed Velocity Describes how fast an object moves Distance traveled in a certain time Units --- m/s Velocity Describes how fast an object moves in a particular direction Displacement traveled in a certain time Units -- m/s and DIRECTION

Speed Velocity Speed = Distance Time Velocity = Displacement Time

Instantaneous Speed Speed at any given instant

Constant Velocity WS If something is moving at a______________________, it means we expect a constant increase in distance over time. Time is increasing to the right, and distance is increasing steadily with time. It moves at a steady velocity.

Constant Velocity WS If something is moving at a constant speed, it means we expect a constant increase in distance over time. Time is increasing the same amount, and distance is increasing (same amount) with time. It moves at a steady, constant velocity.

Constant Velocity WS If something is not moving, a _____________________________ is created.

Constant Velocity WS If something is NOT moving, (forward or backward, but staying at the same distance) a horizontal line is created. A FLAT, HORIZONTAL line (plateau) No change in DISTANCE. (time is still / always moving forward!)

Constant Velocity WS Both the lines show that each object moved the same distance, but the steeper line “got there” before the other one. A _____________________________ indicates a higher velocity. A B

Constant Velocity WS Both the lines show that each object moved the SAME DISTANCE, but the steeper line got there before the other one. A STEEPER SLOPE line indicates a higher velocity. (A traveled the SAME distance, but arrive first - LESS TIME) A B If I take a roller coaster, which one is faster? A or B? Answer: A, steeper line Blue car – slower Red car – faster, steeper

Constant Velocity WS When an object’s _________________ increases, the slope of the line increases.

Constant Velocity WS When an object’s constant velocity increases, the slope of the line increases. How would you describe the motion of a car? - It sped up, it is moving at a higher velocity

Constant Velocity WS What is occurring in this graph?

Constant Velocity WS What is occurring in this graph? 3 2 1 1 – object moving at constant velocity 2 – object is NOT moving 3 – object is moving at a constant HIGHER velocity

Sasha, Kim, and Barry decided to have a 10 km bicycle race after school. Their race results are shown on the time-distance graph below Which cyclist kept a constant speed during the entire race? What was this speed? Which cyclist won the race? What was the winning time? 3. Which cyclist placed last? What was the last place time? 4. Which cyclist started the fastest? How do you know? 5. What was Barry’s average speed? Bell work 9/15