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Let us assume that we placed lot's of ball touching each other in a hollow cylindrical tube, now if we push one ball at the end the ball at the other end move's instantly. So how do the information from one side of the tube travel's to the other side of the tube instantly. and at what speed at it travel's. If it travels at the speed of light so if make a long tube of the length of about $3*10^8$m it would take 1 second to see the effect at the other end assuming that nothing will bend or compress all thing's are ideal? I have read other related question but it didn't contained what I actually wanted to know. So it is not a duplicate.