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This is a question of curiosity, and not for any academic purposes.

Suppose I push a box along a surface that allows it to slide. When I initially start pushing it on one side, how long does it take for the other side of the box to start moving?

Obviously, it's going to be observed as instantaneous, but in the extreme case of a 1 lightyear-long box, I find it hard to believe that all of it would start moving at the exact same time.

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When you push the box you actually apply a force to the atoms(of the box) nearest to you. Then these atoms pushes the next atoms nearest to them and in this way the disturbance you created travel to the other end of the box. This disturbance travel with the speed of sound in the box.

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  • $\begingroup$ Would the end of the box where the force is applied move considerably before the disturbance arrives at the other end? $\endgroup$
    – jm22b
    Jan 27 '15 at 10:16
  • $\begingroup$ @Jacobadtr:when you apply the force on the end of the box , the box will get deformed a little and in that sense yes that end would move to the right(if you apply the force to the right). $\endgroup$
    – Paul
    Jan 27 '15 at 10:34
  • $\begingroup$ See the animation here.physics.stackexchange.com/questions/114397/… $\endgroup$
    – Paul
    Jan 27 '15 at 10:36

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