Consider a sports car which accelerates from 0 ft/sec to 85 ft/sec in 5 seconds (85 ft/sec = 58 mph). The car's velocity is given in the following table. Over which time interval in the average acceleration the smallest?
A)The last
B)The fourth
C)The third
D)The second
E)The first

Question

Consider a sports car which accelerates from 0 ft/sec to 85 ft/sec in 5 seconds (85 ft/sec = 58 mph). The car's velocity is given in the following table. Over which time interval in the average acceleration the smallest? 
A)The last 
B)The fourth 
C)The third 
D)The second 
E)The first

Quizplus · Accepted Answer

The average acceleration is given by the change in velocity divided by the time interval. As the car's velocity increases over time, the change in velocity between adjacent time intervals will also increase. Therefore, the time interval with the smallest average acceleration will be the one where the change in velocity is smallest. Looking at the table, we can see that the change in velocity is smallest between the 4th and 5th time intervals (73-76 ft/sec), so the answer is A) The last.

Consider a Sports Car Which Accelerates from 0 Ft/sec to 85