Main Answer
To find the average velocity of a car that accelerates and decelerates, we need to calculate the total distance traveled and the total time taken, and then divide the total distance by the total time. The given car travels a total distance of:
12 m/s [S] for 5.0 seconds = 60 m [S]
18 m/s [N] for 9.0 seconds = 162 m [N]
15 m/s [S] for 11 seconds = 165 m [S]
Total distance traveled = 427 m
The total time taken is the sum of the times spent traveling at each velocity:5.0 seconds [S]
9.0 seconds [N]
11.0 seconds [S]
Total time taken = 25.0 seconds
The average velocity is calculated as:
Average velocity = Total distance traveled / Total time taken
Average velocity = 427 m / 25.0 seconds = 17.1 m/s [N]. The correct option is A.
Step-by-step explanation
In this problem, we're dealing with a car that accelerates and decelerates, which means its velocity changes over time. To find the average velocity, we need to calculate the total distance traveled and the total time taken, and then divide the total distance by the total time.
This calculation gives us an overall sense of how far the car traveled and how long it took to do so, which allows us to determine an average speed over that entire period.
By understanding how to calculate average velocity in these types of scenarios, we can better analyze and predict the behavior of moving objects in real-world situations. The correct option is A.