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: Boxes of inequal mass connected by spring

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

    Two large crates with masses 640kg and 490kg are connected by a spring (k = 8.1kN/m) and are being pushed across a level frictionless force applied horizontally to the more massive crate. The spring compresses 5.1cm from equilibrium length? What is the applied force?

    2. Relevant equations
    F = -kX

    3. The attempt at a solution

    I am unsure as to what to do right here. As it is a frictionless surface, won't any force move the masses?

    F = -kx = -(8100N/m)(0.051m)= - 413.1N. This is what I figure, but I am pretty sure it is wrong, I don't know how the masses affect this. That is how much force is required to compress the spring by 0.051m, but how much is required to move the boxes as well?
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted