A pole one light year long .

In summary, in a conversation about a pole one light year long and how long it would take to move at one end if pushed at the other end, it was determined that the impulse would travel at the speed of sound in the material, resulting in a time delay of 6700 years for a steel pole. Additionally, it was pointed out that force must be transmitted via molecular interactions and not instantaneously. The conversation was ultimately locked due to incorrect posts.
  • #1
A pole one light year long...

laying in bed last night I had this question pop into my pointy little head.

If I had a pole one light year long sitting between points A and B and I pushed it forward one foot from point A toward point B how long would it take to move at point B?

I've got an answer, but I'll wait to see what the people smarter than me have to say.
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  • #2
That's a meaningless answer, funker, since no such thing exists.

Bender, it the impulse would travel at the speed of sound in that material. For example, if the pole were steel, with a speed of sound of 4500m/s, it would take 6700 years for the impulse to reach the other end of the pole.
  • #3
FUNKER said:
it would be instantaneous, provided a rigid body system

Err, please don't answer like that. You are proposing faster than light communication here. If it were instantaneous, then we could send morse (poking) instantaneously, whereas light would take one year. If you hit one end of stick with a hammer, would the other end hear it instantaneously? No. You must think of the interaction at a molecular level.

EDIT: Russ beat me to it.
  • #4
Huh? No, minijumbuk. You are simply wrong. Force has to be transmitted via molecular interactions. If forces propagated instantaneously, there'd be no sound because objects wouldn't oscillate. Striking a large bell with a hammer would just make it swing back and forth.

Gravity is different, but it still propagates at the speed of light.
  • #5
I have deleted some blatentely incorrect posts.

Locking since the question has been answered and there is no point in further discussion.

1. How can a pole be one light year long?

A light year is a unit of measurement used in astronomy to measure distances. It is defined as the distance that light travels in one year, which is approximately 9.46 trillion kilometers. So, a pole one light year long would be a very long pole indeed!

2. How would a pole one light year long be supported?

It would be impossible to physically support a pole one light year long, as it would collapse under its own weight. However, in theory, it could be supported by advanced technology or materials with incredible strength and stability.

3. How long would it take for light to travel along a pole one light year long?

Since light travels at a speed of approximately 299,792,458 meters per second, it would take one year for light to travel along a pole one light year long.

4. What would happen if you tried to move a pole one light year long?

Moving a pole one light year long would be impossible due to its immense length and weight. If it were somehow moved, it would cause significant disturbances in space and time due to its mass and the speed of light.

5. How would a pole one light year long affect the Earth's gravity?

A pole one light year long would have an immense amount of mass, which would greatly affect the Earth's gravity. It could potentially cause significant disruptions and changes in the Earth's orbit and other celestial bodies in our solar system.

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