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?(adsbygoogle = window.adsbygoogle || []).push({});

The density of the rod is the same at all points.

I believe that logically the rod would continue to accelerate but that begs me to ask how fast this "wave" of "force-information" is travelling? Is it a sound wave (It appears to me) or is it travelling at C? (Here I assume that the speed of sound within the rod is less than C)

Given that, here's my follow up question (a bit more interesting I suppose)

We define U, as the Net Yank or Jerk * Mass. Where Jerk is the time derivative of acceleration or the third time derivative of position.

U = JM or U = [itex]\frac{dA}{dt}[/itex]M

So a Yank of 100 Newton Meters per Second is being applied continuously to our same 5 Kg cylindrical rod (1 light year across) (whose rest-density is the same at all points) causing it to increase its rate of acceleration at 20 meters per second cubed. Suppose this Yank was removed? Does that mean this rod would continue increasing its rate of acceleration for a period of time before coming to halt?

Thanks! P.S. Sorry for the Grammar mistake in the title

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# A Moving Body

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