Respuesta :

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