Calculating Car Distances: Uncertainty in Car Gaps and Lengths

AI Thread Summary
The discussion focuses on calculating the total distance between cars when stopped, considering the average car length and stopping gap. The average car length is 5.1 ± 0.5m, and the average gap is 1.45 ± 0.25m. To find the minimum and maximum distances for a lineup of cars, the smallest and largest values of both the car length and gap must be used. For example, with ten cars, the minimum distance would be calculated using the shortest car length and nine times the smallest gap. The first car is assumed to have no gap to another vehicle, simplifying the calculation.
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Homework Statement


Drivers that come to a stop leave different amount of gaps between their car and the car in front. It was found that the average gap was 1.45m, but as the values varied, the uncertainty was 25cm. It was also reported that the car is 5.1 ± 0.5m in average. What is the range of distances from the bumper of the first car to the back bumper of the last one, if the cars were to line up when it comes to a stop?


Homework Equations



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The Attempt at a Solution


Add the avg gap and the avg length of the car?
 
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You need the range of distances. So this would be the shortest possible distance to the longest.

Firstly, how many cars are there?

Average length of a car is 5.1 ± 0.5m
Average stopping gap is 1.45 ± 0.25m

So you take the smallest possible values of those two and add up to give the minimum distance and you take the largest possible values to get the maximum.
 


Thank you very much. Can you give me an example if 10 cars were to line up?
 


Well for ten cars it would be ten times the shortest possible length of a car (5.1 - 0.5) and nine times the smallest stopping gap (1.45 - 0.25).

Now, I'm assuming the first car doesn't have a stopping gap to another vehicle here. Otherwise it would be ten times the stopping gap.
 


thanks!
 
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