An advertisement claims that a particular automobile can "stop on a dime". What net force would actually be necessary to stop an automobile of mass 850kg traveling initially at a speed of 56.0km/h in a distance equal to the diameter of a dime, which is 1.8cm ?

Answer 1

a = (V^2-Vo^2)/2d
a = (0-(56)^2)/0.036 = -87,111 m/s^2

F = m*a = 850 * (-87,111)=-74,044,444 N.