Concept explainers
One drop of oil falls straight down onto the road from the engine of a moving car every 5 s. Figure OQ2.1 shows the pattern of the drops left behind on the pavement. What is the average speed of the car over this section of its motion? (a) 20 m/s (b) 24 m/s (c) 30 m/s (d) 100 m/s (e) 120 m/s
Figure OQ2.1
The average speed of the car over the given section of motion.
Answer to Problem 1OQ
Option (b).
Explanation of Solution
Write the equation for the average speed.
Here,
Since there are five time intervals during the given section of motion and each time interval is
Substitute
Conclusion:
Since the average speed of the car during the given section of motion is
Since the average speed of the car during the given section of motion is not
Since the average speed of the car during the given section of motion is not
Since the average speed of the car during the given section of motion is not
Since the average speed of the car during the given section of motion is not
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Chapter 2 Solutions
Principles of Physics: A Calculus-Based Text
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