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: Horizontal force problem

  1. Feb 26, 2010 #1
    1. The problem statement, all variables and given/known data

    A 2.7 kg block initially at rest is pulled to the right along a horizontal, frictionless surface
    by a constant, horizontal force of 17.3 N. Find the speed of the block after it has
    moved 4 m. Answer in units of m/s.

    2. Relevant equations

    3. The attempt at a solution
    17.3N/2.7Kg=6.40741m/s now what
  2. jcsd
  3. Feb 26, 2010 #2
    Re: force

    since the force is constant , this implies that the acceleration is constant as well .. so in this case you can use one of the kinematic equations ..

    vf = vo + a*t .. (vf=final velocity,vo=initial velocity,a=acceleration,t=time)
    vf^2 = vo^2 +2ax (x = distance of travel)
    x = vo*t + 0.5*a*t

    you have now a, in the question it is said that the block initially at rest(what that tells you about the initial velocity?), you have x , I think with these quantities you can find the final velocity(in other words, the velocity after the block has moved x=4m) ..
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook