1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    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!

2 Part Kinematic Equation Problem

  1. Sep 26, 2010 #1
    1. The problem statement, all variables and given/known data
    A car driving at a constant speed of 75 ft/s passes a police car that is initially at rest. If the police car decides to give chase
    A) What rate would the police have to accelerate to catch up with the other car in 12 seconds?
    B) What is the police car's speed at the end of the 12 seconds?

    2. Relevant equations
    Use Kinematic Equations

    3. The attempt at a solution
    The first car's displacement would be 75 ft/s * 12 seconds = 900 feet? So if I use X = Vot + 1/2(at^2)that means that acceleration of the second car would have to be 12.50 ft/s Is this the correct? Or am I way off? So if the acceleration = 12.50 ft/s I use V = Vo + at and end up with Final V = 150 ft/s ? That just doesn't sound right to me, could you please try to explain what I'm doing wrong?
  2. jcsd
  3. Sep 26, 2010 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Looks good to me. You're doing nothing wrong.
  4. Sep 26, 2010 #3
    Well thank you :) I'm trying really hard to learn Physics. It's difficult for me to learn, but it's very interesting.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook