# Radical Equations - Car Length and Stopping Distance

Radical Equations Project: Car Length and Stopping Distance

See the attached file for details of this project.

https://brainmass.com/math/basic-algebra/radical-equations-car-length-stopping-distance-181876

## SOLUTION This solution is **FREE** courtesy of BrainMass!

The solution file is attached.

Car length = 4.8 m = 15.75 ft

s (In miph) L in feet = (s/10) ï‚´ Car length r(L) = 2ïƒ–(5L) in miph

20 31.5 25.10

30 47.25 30.74

40 63 35.50

50 78.75 39.68

60 94.5 43.47

70 110.25 46.96

From the last four rows of the table, we find that the "1 car length per 10 miph" guideline suffices only for cars traveling at speeds below and up to 30 miph. In speeds higher than 30 miph, the length of the skid marks left behind as measured by the police in test cases is higher, which only goes to mean that the prescribed "1 car length per 10 miph" gap is no longer safe.

Another way of looking at the results is by directly comparing the permissible speed that will allow a car to stop within the prescribed distance given in column 2. At speed 35.5 miph, for example, the stopping distance is 63 feet and obviously a car traveling at 40 miph will not be able to avoid hitting the car in front.

https://brainmass.com/math/basic-algebra/radical-equations-car-length-stopping-distance-181876