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: Velocity of a boulder

  1. Oct 7, 2007 #1
    1. The problem statement, all variables and given/known data

    A slight earth tremor causes a large boulder to break free and start rolling down the mountainside with a constant acceleration of 5.2 m/s^2. What is the boulder's velocity after 5.0s.

    2. Relevant equations

    I used: v2 = v1 + a x Δt

    3. The attempt at a solution

    v1 = 0 [because it started to break free]
    a = -5.2m/s^2 [because of the sign convention down]
    Δt = 5.0s
    v2 = ? [because it is finding velocity after 5.0s]

    ok it was v2 = 0 + (-5.2m/s^2)(5.0s)
    v2 = -26 m/s

    Am I correct or have a done a simple mistake that would impact my answer?
  2. jcsd
  3. Oct 7, 2007 #2


    User Avatar
    Science Advisor
    Homework Helper

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook