Physics
posted by Maryam on .
Problem 4 Speedy car, driving at 30 m/s. The driver suddenly observes a slowmoving van 155 m ahead traveling at 5 m/s in the same direction. The driver of the car immediately applies the brakes causing a constant acceleration of 2 m/s2 in a direction opposite to the cars velocity.
a) After the driver of the car applies the brakes, at what time the car will collide with the van?
b) Take x= 0 at the location of the car when the brakes applied, where does the collide with the van?

if the collide, they have traveled the same distance in the same time.
distance van=155+5t
distancecar=30t1/2 *2*t^2
set them equal, solve for time t.
then using t, solve for car distance. 
t = 10.5 s