Final answer:
The examples provided are classified as either speed or velocity based on whether a direction of travel is specified or not. A speedometer measures speed, whereas dividing the total distance traveled by time calculates average speed, which is equal to the magnitude of average velocity only if there is no change in the direction of travel.
Step-by-step explanation:
In addressing whether the examples provided reflect speed or velocity, it's important to understand the distinction between these two concepts. Speed is a scalar quantity that refers only to how fast an object is moving, regardless of its direction, while velocity is a vector quantity that includes both the magnitude of the speed and the direction of motion.
- A. Driving interstate 70 from Aurora to Vail, Co - Velocity (The direction from Aurora to Vail is specified.)
- B. Walking 1 kilometer north from East Middle School - Velocity (The direction is north.)
- C. Rolling a bowling ball down a bowling alley - Speed (No specific direction is given.)
- D. Running the 800 relay (2 laps) at the Hinkley High stadium track - speed (No specific direction is indicated because the final displacement is zero, assuming the start and end points are the same.)
- E. Bouncing straight up into the air from a large trampoline - Velocity (Direction is specified as upward.)
- F. Climbing up a rock wall - Velocity (Direction is upward.)
The speedometer of a car measures speed because it only displays how fast the car is traveling without any directional information. Conversely, a car's odometer measures distance traveled but not displacement. When you divide the total distance traveled (as determined by the odometer) by the elapsed time of the trip, you are calculating average speed. Average speed and the magnitude of average velocity are the same only if the car does not reverse direction during the trip.