# J.C.MacSwell

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Temporarily.
2. ## Foucalt pendulum question

Yes, but it is also (like everything everywhere) in a (read infinitely many)rotating reference frame/s. We usually don't pick them for obvious reasons. Edit: in your example the body (runner) is in an inertial frame and at rest in that frame. So these pseudo forces/effects vanish. If we picked rotating reference frames as may sometimes be useful in engineering we may require pseudo force/effect "adjustments" to correctly use Newton's Laws.

7. ## Question

As to picking a spot on the moon the spin effect is obviously small due to the 27.3 day rotation time. The tidal effect is also small but I think it would be tens or hundreds of times larger in this case. Sorry if I'm guessing while you guys are obviously doing the work. I've enjoyed following this thread and thought I might at least stick my neck out on an educated (?) guess.
8. ## Questions about Special Relativity

It's kind of like "home ice advantage". You come to my rink and I'm the cagey veteran and you're the young punk. If I come to yours then You're older and I'm younger. Apologies to relativists and hockey fans everwhere for a bad analogy,
9. ## Question

1 second later he will be travelling at 9.78 m/s (in the downwards direction) but will have dropped only 4.89 metres. His horizontal/rotational velocity/vector should exceed that of the Earth.
10. ## Question

There is an effect. But I think it's smaller and in the opposite direction. (than what J5 was describing)
11. ## Location of Big Bang?

Also true if it's finite unbounded.
12. ## Light speed travel

They're tired, they're out of breath...but they keep on going.
13. ## The accelerating universe - Cosmic inflation

Does this make it a "best guess or a Theory (capital "T"). Also, what would you bet that it is correct (odds not \$) I'm at 50% and dropping. I am at heart a Steady State guy (brain only allows 25% but it's rising) but have no consistent mathematical model to base it on. It is not even at the "half baked" stage and could end up closer to Big Bang (which I'm betting is twice as likely at this point). I appreciate your posts. They are informative, challenging and fun. I wish I had more time to learn the math at the level of some of the posters here.

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17. ## Question

I'm not convinced Mach was wrong either. I have a butt cheek on each side of that fence. I don't think he had a space-time view of space and time however.
18. ## Question

I think that, if this is the case, then they "contribute" in such a way as to define an inertia frame. In other words they all cancel (balance would be a better term because if Mach was right we might all have less inertia) and can be ignored.
19. ## Question

Should be very close to the centre of gravity of the earth/moon system.
20. ## Question

I was referring to a hypothetical moon. Spin (or tidal effects) would tend to make it non-spherical.
21. ## QG units

Let's call an E-31 black hole "Olber's Mass". If you look far enough into space, eventually you'll see one!
22. ## The accelerating universe - Cosmic inflation

Was the evidence of the acceleration that the redhift was not "as expected" for the galaxies/clusters viewed at that distance/age?

You have a "clue". If it has a one day half life it has a 50% chance of decaying in the "next" 24 hours.
24. ## Question

If the moon is a perfect sphere it's probably not spinning. If it's spinning anyway there should be an effective weight difference. If it's orbiting the earth there should be tidal effects making you lighter on the point closest to Earth and also lighter (by almost as much) on the point farthest from Earth.

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