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: Displacement of spring of a block going down an incline

  1. Oct 12, 2011 #1
    1. The problem statement, all variables and given/known data
    An inclined plane of angle θ = 20.0° has a spring of force constant k = 455 N/m fastened securely at the bottom so that the spring is parallel to the surface as shown in the figure below. A block of mass m = 2.71 kg is placed on the plane at a distance d = 0.330 m from the spring. From this position, the block is projected downward toward the spring with speed v = 0.750 m/s. By what distance is the spring compressed when the block momentarily comes to rest?

    2. Relevant equations

    Dig= mg[h + x(sin20.0)]

    3. The attempt at a solution
    Kf,Disp, and Dfg all Equal zero
    so by substitution:

    -1/2mv^2+1/2kx^2-mg[h + x(sin20.0)]=0

    which simplifies to

    My answer is .226, which is the incorrect answer. What am I doing wrong?

    Last edited: Oct 12, 2011
  2. jcsd
  3. Oct 13, 2011 #2
    I forgot to post the picture. Here it is:
    Last edited: Oct 13, 2011
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook