1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Need help with simple acceleration problems.

  1. Oct 7, 2007 #1
    Here's one:

    Craig got up to 133.5 km/h getting around a slower vehicle within the length of the passing lane. He then spotted a police cruiser coming around the corner and hit the brakes, slowing to 100 km/h in 0.9 seconds. How much distance did he travel in this time

    So I'm pretty much confused with accleration problems and identifying intial velocity and final velocity. I kow that t=.9 secs. So is the initial velocity 133.5 km/h and final velocity is 100 km/h?

    Would I first use the delta s=vi(t)+ 1/2(a)t^2 equation to find the displacement of when he slowed down?
  2. jcsd
  3. Oct 7, 2007 #2


    User Avatar
    Homework Helper


    to use this you need to assume that acceleration is constant. at this stage you have only 3 known variables: u, v and t. but from these you can work out the average (de)acceleration
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Need help with simple acceleration problems.