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: Determine the acceleration and position of the bullet

  1. Sep 30, 2009 #1
    1. The problem statement, all variables and given/known data

    The speed of a bullet as it travels down the barrel of a rifle toward the opening is given by v = (-4.80 107) t 2 + (2.45 105) t, where v is in meters per second and t is in seconds. The acceleration of the bullet just as it leaves the barrel is zero.
    (a) Determine the acceleration and position of the bullet as a function of time when the bullet is in the barrel. (Use t as necessary and round all numerical coefficients to exactly 3 significant figures.)

    3. The attempt at a solution

    acceleration = -9.6*10^7t + 2.45 * 10^5

    position of bullet with as a function of time = -16000000t^3 + 122500t^2

    I am getting the second one wrong and I do not know why. Displacement is the integral of velocity but it keeps saying I am wrong. I have tried using scientific notation, and a variety of other things, but always get it wrong.
  2. jcsd
  3. Sep 30, 2009 #2
    Re: kinematics

    nvm I got it. I didn't use significant figures
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook