1. Limited time only! Sign up for a free 30min personal 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!

Homework Help: Jet Planes

  1. Sep 8, 2010 #1
    1. The problem statement, all variables and given/known data

    A jet plane is cruising at 300 m/s when suddenly the pilot turns the engines up to full throttle. After traveling 2 km, the jet is moving with a speed of 400 m/s. What is the jet's acceleration (in m/s/s) during this interval assuming the acceleration to be constant?

    2. Relevant equations

    I was thinking that in order to go further you would have to solve for the seconds? So I used v=m/s and solved for s, which was then 5s. But I'm not sure where to go from there?

  2. jcsd
  3. Sep 8, 2010 #2


    User Avatar
    Homework Helper

    Initial and final velocities are given. Displacement is given. Find the kinematic equation which relates Vi, Vf, x and a. And solve for a.
  4. Sep 9, 2010 #3
    But the only kinematic formulas I find include time, which isn't given.
  5. Sep 9, 2010 #4
    Well, I tried vf=vi+a(t) but I got 20m/s/s, which was wrong.
  6. Sep 9, 2010 #5


    User Avatar
    Homework Helper

    v2f - v2i = 2as

    Substitute the values and find a. Here s = 2000 m.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook