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: Find acceleration from distance and time, with a twist

  1. Sep 10, 2013 #1
    1. The problem statement, all variables and given/known data
    A drag racer starts from rest and covers the last 40 meters of a 400 meter race in 0.20 seconds.
    a) What was his acceleration
    b) He beat another driver by 0.05 seconds, what was the second drivers acceleration?
    c) How far was the first driver ahead when he crossed the finish line?

    Acceleration is constant for both drag racers.

    2. Relevant equations

    All kinematics equations can be used.

    3. The attempt at a solution

    I tried to create an equation using variables but this proved tricky. I am unsure of where to start and how to proceed. Also we were given a hint: t2=t1-0.20

    _________t2______/(40 m)/
  2. jcsd
  3. Sep 10, 2013 #2
    Conceptually this is a simple problem - it just require the careful application of some basic facts about one-dimensional motion and knowledge of the basic kinematics formulas. It's probably easiest to work backwards.

    You'll need the following formulas:

    $$Δx = v_{1} Δt + \frac{1}{2} a (Δt)^{2}$$
    $$v_{2} = v_{1} + a Δt$$
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted