Immovable Rod Question

[Theone0581]

Okay so this might have been asked before, but just in case it has not.

If one was to active an immovable rod and leave it there over a long period of time, would the rod move with the planet as it rotates? Or would it collide with sold matter.

 

[Alexander123]

I think the term immovable rod is a term which is simply given to the item, not necessarily implying that it doesn't move.

In the same way that the sun is going to be with us for ever even though in fact, it will only be with us for millions of years but for us it is the equivalent of forever.

I don't think it really matters which way you rule.

Although I suppose you could rule that the magic gradually weakens over time for various reasons.

 

[Dannyalcatraz]

Given the absolute speed at which planets rotate and orbit, immovable rods are only immobile relative to the planet's inhabitants. If they were absolutely immobile, once activated, they would slam...no, more accurately, something on or of the planet would slam into the rod at tens of thousands of MPH.

 

[Theo R Cwithin]

I always assume the intention is that the Rod stays put relative to ground. That way you don't have to worry about it if your fantasy world rotates like earth, stays put like the old geocentric view, or lurches along on the back of a turtle.

Another way to look at it: at the Earth's equator, the rotation speed is around 1000 miles per hour-- which means the Rod wouldn't seem very Immovable for those trying to use it. [edit: ninja'd by DannyA on that one!]

Things like that are why, imho, thinking about magic items in physics terms doesn't usually end well.

 

[Theone0581]

Things like that are why, imho, thinking about magic items in physics terms doesn't usually end well.

Thats why this is such an interesting topic.

In my game, the rod stays in place regardless of how fast the planet is moving, it makes things lets complicated and allows players to focus more on the thing at hand.

For argument purposes, we will say that the planet that this rod is on will be going at the exact speed as the planet that we live on. (earth, assuming we all live on earth )

 

[Theo R Cwithin]

In that case, it's easy-- but you have define "immovable" relative to what, first!

If you're dealing with Earth in this Universe, and if you mean the Rod is immovable to center of the earth, then at the equator the Rod zips eastward at 1000mph, and that drops to zero the close to the poles you go, where it would just slowly spin in a circle over one day's time.

If you mean it's Immovable relative to the Sun, then there's that motion, plus another 65000mph that the Rod will move away from you! Measure relative to the center of the galaxy, and you have to consider another 400,000mph or so in some direction...

If you add up all the motions in the universe, and assume the Rod is activated when the stars are aligned just perfectly, then the thing will zip off at something like 2million mph in some direction.

So yeah, not really very Immovable for the guy trying to use them as a ladder. But it probably could do a LOT of damage to whoever it hit (or, more accurately, whoever hit it) if you timed it just right.

 

[Theone0581]

haha! Your explanation really cracks me up! Thank you for that. I am still chuckling.

 

[Thunderfoot]

I would think that the rod would be in a micro geo-synchronous/geo-stationary orbit. The object stays in relative location with respect to it's current location without having to be 33.3 miles above the earth's/planet's surface; that's why it's a magic item.

For most people the act of being stationary is the magic, of course it isn't. The REAL magic is the close proximity to the surface of the planet and being to maintain the illusion of geo-synchronicity. Yeah, leave it up to someone who used to study satellite theory.

 

[Dannyalcatraz]

There you go again, proving that some drummers can do more than count to four.

 

[Rakusia]

immovable rod is a misnomer. it actually moves so fast it can keep up with the earths rotation. but this brings to question does the game world rotate?