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Calling all nerds- MATH QUESTION related to speeding

2133 Views 12 Replies 8 Participants Last post by  mpd61
Can someone tell me the formula to use to equate speed in MPH to how many feet it will take in stopping distance? Thanks in advance
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bpd19, you are asking a very broad question. You need much more info to come up with the answer. Here is an example

A vehicle traveling 50 miles per hours is traveling 73.5 feet per second (1.47 X M.P.H.)
Perception time is 1.5 seconds
We multiply 73.5 X 1.5 = 110 feet
D=111 feet
Total Distance is 110 feet + 111 ft = 221 Feet

Remember f is the drag factor. I used .75 for average travelled dry pavement, that can change dramatically based on the drag factor. You have to either do test skids or use a drag sled. Also you should computer for m=grade and super-elevation to get an accurate number.

Hope this helps, recon class!!
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