Suppose that a woman driving a Mercedes zooms out of a darkened tunnel at 41.5 m/s. She is momentarily blinded by the sunshine. When she recovers, she sees that she is fast overtaking a truck ahead in her lane moving at the slower speed of 12.9 m/s. She hits the brakes as fast as she can (her reaction time is 0.32 s). If she can decelerate at 2.3 m/s2, what is the minimum distance between the driver and the truck when she first sees it so that they do not collide?
V=Vo + at
X=VoT + 1/2at2
V2=Vo2 + 2ax
(If a 2 is after a letter then it means squared)
The Attempt at a Solution
First I think you need to find the time.which is 41.5/2.3 = 18.04 seconds. Then you need to add on her reaction time (.32 sec) to get 18.36 seconds. Then I used the "X=1/2(Vo +V)T" to get 380.92 meters. I'm not sure if that is correct though. What do you guys think?