View Single Post
Feb29-12, 08:08 PM
P: 1,555
Quote Quote by Frogeyedpeas View Post
So Imagine that a force of 100 N is being applied continuously on face of 5 kg cylindrical rod (1 light year across) causing it to accelerate at 20 m/s^2. If the force was abruptly removed would the rod continue to accelerate a noticeable period of time before coming to a halt?
The back of the rod (where the force was applied) would immediately stop accelerating (or perhaps within a Plank time unit), the front would conceivably would not even have started to accelerate (and depending on the material, if ever) if the applied force stopped before the end would have been reached carrying a wave with a velocity right about the speed of sound.