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: Kinematics problem

  1. Aug 30, 2008 #1
    A particle moves along a straight line with accel. a = 2[tex]\sqrt{v}[/tex] where v = [tex]\frac{dx}{dt}[/tex] is the velocity. At t = 2s, the particle is located at x= (64/3)m with velocity v = 16m/s. Find the location and acceleration at time t = 3s (hint: integrate)

    Now, if the differential equation is dv/dt = 2[tex]\sqrt{v}[/tex]. I donĀ“t know how to solve such an equatoin (because of the square root). But then I thought v must be constant for the integration to work, but that would mean that the acceleration would be zero and that makes no sense. I need help.
  2. jcsd
  3. Aug 30, 2008 #2
    never mind, I figured it out as soon as I clicked submit post.

    dv over the sqrt(v) = 2dt

    No w8, this makes no sense, if you integrate you get 2sqrt(v) = 2t + c
    Last edited: Aug 30, 2008
  4. Aug 31, 2008 #3
    Square both sides of that expression and integrate again. You have enough data to find the constants.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook