Answer:
Your foot brake must be able to stop car within 5.18 m
Explanation:
[tex]d = s^{2} / (250 * c_{f} )[/tex]
d is breaking distance.
s is speed in km/h
[tex] c_{f}[/tex] is coefficient of friction normally 0.8
250 is constant.
Give the speed in mile first convert it to km/h
[tex]1 km = 1.60934 mile[/tex]
speed in km= 20 * 1.60934
s =32.186 km/h
[tex] d=32.186^{2} / (250 * 0.8)[/tex]
d= 5.18m