Question for physics guru
- Thread starter salami1212
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homework was never interesting
Yeah, the theory is that we would not feel the effect on the change from the sun's mavity until around 8 minutes.
If the bottom box was moving that quickly, the amount that the top box fell would defilitely be so small that the top box would still be able to sit on top of it.
But to answer your original question, yes things do fall instantly, but they start off slowly and accelerate with time.
Soldato
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Well, for it to happen any sooner would at least violate relativity.
That makes the question invalid and unphysical.
When reaching the speed of light, time itself slows down.
So if some thing is falling that fast it is about to take over light, time will simply slow it down to just shy of light speed, because it's a physical impossibility to pass light.
Imagine a train hurtling along at light speed, then some one inside the train walks forward to the front, if they passed light speed they would cease to exist, how can they be there and their reflection/light not be? So time slows down to allow them to move forward.
So nothing can gravitate faster than light
Hhhmm from college......
Unless you beleive in gravitons and the like (which most scientists don't) then mavity is an effect of geometry, i.e. mass effecting the curvature of space. To say it travels at x speed is misleading.
Unless you beleive in gravitons and the like (which most scientists don't) then mavity is an effect of geometry, i.e. mass effecting the curvature of space. To say it travels at x speed is misleading.
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Soldato
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But changes in that geometry cannot propagate instantaneously.
I changed my original post....
Anyway yes your probably right which would mean that the "speed" of it depends on the mass of the body in question. But its still being talked about in the wrong terms.
Light cannot escape from a blackhole (in most circumstances) this doesn't mean that mavity travels faster than light at best it means that the force of mavity in the case of the black hole curves space up so much that it cant escape.
Anyway yes your probably right which would mean that the "speed" of it depends on the mass of the body in question. But its still being talked about in the wrong terms.
Light cannot escape from a blackhole (in most circumstances) this doesn't mean that mavity travels faster than light at best it means that the force of mavity in the case of the black hole curves space up so much that it cant escape.
mavity exerts a measurable force on photons (light), similar to a lens bending the light. The force of mavity is related the mass of the photon and the mass of the black hole (black hole being many many times more massive). So yeah the force of mavity from a black hole is so great that not even photons can escape its grasp
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Soldato
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prove it
Well the entirety of modern physics is built upon that assumption (and by extension, all other sciences too), so…
They mean that gravitational fields propagate at the speed of light. For example, we're 8 light minutes away from the sun. If the sun spontaneously popped out of existence, we'd continue orbiting the point where it was for 8 minutes.
Isnt this already proven with the card shot in half thing.
Here.
http://www.artsology.com/edgerton_photography.php
Magical floating cards?
Here.
http://www.artsology.com/edgerton_photography.php
Magical floating cards?
Out of curiosity, what would happen then?