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AP Physics Chapter 2 Study Guide Kinematics: Speed and Velocity Displacement: A change from one position to another position.
Average Speed:the distance traveled divided by the time it took to travel the path.
Sample Problem 1 You
drive a beat-up pickup truck along a straight road for 8.4 km at 70
km/hr, at which point the truck runs out of gasoline and stops. Over
the next 30 minutes, you walk another 2.0 km farther along the road
to a gasoline station. a) What is your overall displacement from the beginning of your drive to your arrival at the station?
b) What is the time interval Δt from the beginning of your drive to your arrival at the station?
c) What is your average velocity from the beginning of your drive to your arrival at the station? Find it both numerically and graphically.
d) Suppose that to pump the gasoline, pay for it, and walk back to the truck takes you another 45 minutes. What is your average speed from the beginning of your drive to your return to the truck with the gasoline?
Sample Problem 2 Plot the position v. time graph for an elevator that is initially stationary, then moves upward, and then stops. Plot velocity v. time for the elevator. Plot acceleration v. time for the elevator.
Constant Speed
Constant speed means you travel the same distance for each time interval. The equation is the same as the one you used in Algebra d = rt.
What do you notice about the bee traveling at a constant speed?
What is the difference between these graphs?
How do you calculate the distance traveled from a velocity v. time graph?
Formula for Instantaneous
Speed
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