On Sat, 27 Aug 2005 03:09:20 GMT, wrote:

On Fri, 26 Aug 2005 12:05:53 +0200, Kim B wrote:

If you accelerate a rigid rod of 1 ly by pulling the front with
approx. 9.5 m/s/s (a little less than normal gravity), the
acceleration of a point at the rod as seen in the rest system will
approach infinity as the point's position approches 1 ly from the
front end (and this is of course the point, where the rod will break,
no matter how strong it is)

Kim
Let's look at things with respect to the problem I posted, please post
your answer to the following questions.
1. If I place all points along the length of a steel rod 1 meter in
diameter and 10 meters in length onto a conveyer belt moving 3 meters
/ second, will the rod break?
2. If the rod is 100 meters in length when I do this, will it break?
3. If the rod is 1000 meters in length when I do this, will it break?
4. If the rod breaks, what length does it have to be before it
breaks, and at what point of the rod will the break occur?
5. If the rod is only 1 cm in diameter, does it break at a different
point or at a different length?
Thanks,
David


Forget about the belt. Read the link I sent you a while a go, learn to
understand spacetime diagrams, use them to understand what happens
when a RIGID rod is accelerated, and why an event horison occurs
approx. 1 ly down the rod when the front end is accelerated 9.5 m/s/s.
Thats the way of learning, it takes a few hours (I learned a lot this
way).

Kim