Observe the animation of the three cars below. Use the animation to answer the three questions. (If necessary, review the definition of acceleration.)
1. Which car or cars (red, green, and/or blue) are undergoing an acceleration? Study each car individually in order to determine the answer.
If you inspect each car individually, you will more likely notice that only the green and the blue cars accelerate. The red car moves with a constant speed, covering the same distance in each second of the animation.
The green and the blue cars are speeding up, thus covering an increasing distance in each second of the animation.
2. Which car (red, green, or blue) experiences the greatest acceleration?
The blue car has a greater acceleration. It is changing its velocity at a more drastic rate.
3. Consider the position-time graph at the right. Each one of the three lines on the position-time graph corresponds to the motion of one of the three cars. Match the appropriate line to the particular color of car.
The red car is moving with a constant velocity and must correspond to object B which has a constant slope.
The green and blue cars have a changing velocity and must correspond to lines with a changing slopes - objects A and C. The green car is object C which has a more gradually changing slope than object A (blue car).
For more information on physical descriptions of motion, visit The Physics Classroom Tutorial. Detailed information is available there on the following topics: