How would a "long" object move? My question is seemingly simple. Let us suppose that we had an unbreakable/inflexible rod whose length was 11.8 million miles in length (one light-minute). Now assume that we applied enough force at one end of the rod to move the entire rod altogether. As nothing can travel faster than the speed of light, how long would it take for the opposite end of the rod to move? Does the motion of the rod become a wave?