- #1

fantolay

- 5

- 0

## Homework Statement

Assume you are driving at the speed limit V

_{o}. As you approach an intersection 22m wide, you see the light turn yellow. During your reaction time of .6s, you travel at a constant speed as you recognize the warning, decide whether to stop or to go through the intersection, and move your foot to the brake if you must stop. Your car has good brakes and can accelerate at -2.4m/s

^{2}. Before it turns red, the light should stay yellow long enough for you to be able to get to the other side of the intersection without speeding up, if you are too close to the intersection to stop before entering it. (Suggestion: You may find it easier to do part (a) after part (b).)

a) Find the required time interval DeltaT

_{y}that the light should stay yellow in terms of V

_{o}.

Evaluate answer for...

b) V

_{o}= 8m/s

c) V

_{o}= 11m/s

d) V

_{o}= 18m/s

e) V

_{o}= 25m/s

Evaluate your answer for...

f) V

_{o}approaching zero

g) V

_{o}approaching infinity

h) Describe pattern of variation of DeltaT

_{y}with V

_{o}. Account for answers to parts (f) and (g) physically.

i) For waht value of V

_{o}would Deltat

_{y}be minimal?

j) What is the minimum time interval for part (i)?

## Homework Equations

Probably the big 4 will be necessary in some form or another.

## The Attempt at a Solution

I have no idea where to begin with this problem. I really don't even understand what it is asking and what is going on in the scenario.

I really appreciate any help.

Thanks guys.