The problem statement, all variables and given/known data The minimum safe distance between vehicles on a highway is the distance a vehicle can travel in 2.0s at a constant speed. assume that a 1.2x10^3 kg car is travelling 72km/h when the truck ahead crashes into a northbound truck and stops suddenly. a) if the car is at the required safe distance behind the truck, what is the separation distance? b) If the average net braking force exerted by the car is 6.4x10^3 N [N], how long would it take the car to stop? c) Determine whether a collision would occur. Assume that the driver's reaction time is an excellent 0.09s. The attempt at a solution 3a) d = (vi+vf/2) t = (1200+0/2) (2) = 1200 m b) Fnet = m*a -6.4x10^3 = (1.2x10^2)a a = -5.3 m/s^2 a = vf-vi/t -5.3 = 0-1200/t t = 226.4s c) d = vit + 1/2at^2 d = (1200)(0.09) + 1/2 (-5.33)(0.09)^2 d = 108m Which is the distance travelled in reaction d = vit + 1/2at^2 = (1200)(225) + 1/2(-5.33)(225)^2 = 2.7x10^5 - 134915 = 135084m m d = 13504 + 108 = 125192 m so a collision would occur Is this correct?