- #1
inevitable?
- 6
- 0
Homework Statement
a motorist is driving at 20m/s when she sees that a traffic light 200m ahead had just turned red. she knows that this light stays red for 15s, and she wants to reach the light just as it turns green again. it takes her 1.0s to stop on the brakes and begin slowing. what is her speed as she reaches the light at the instant it turns green?
The answer is 5.71 m/s.
Homework Equations
d= ( v1+v2/2) (t)
d= v1(t)+1/2(a)(t2)
The Attempt at a Solution
Tried to find v2 by rearranging the first equation.. tried finding a to possibly use it as another variable in an equation.. nothing is working