Solve Your Speeding Dilemma: Calculating Braking Time and Distance

[sabresfan2000]

The brakes on your automobile are capable of creating
acceleration of 14 ft/s2. If you are going 82 mi/hr and sud-
denly see a state trooper, what is the minimum time required to get your car to 55 mi/hr?

How far do you travel while returning to the legal speed limit?

 

[daveb]

You'll have to post where you're stuck at so we can provide the right direction. Just giving the answer won't help you in the long run.

 

[sabresfan2000]

i don't know how to start the problem.

 

[tiny-tim]

hi sabresfan2000!

use the standard https://www.physicsforums.com/library.php?do=view_item&itemid=204" equations …

show us what you get ​

 

[daveb]

You've been given acceleration, final velocity, and initial velocity, and are looking for time, right? Take a look at your equations of motion.