Soldato
It's 8.3 light-minutes away, so in day time, 8.3 minutes, at night, 8.3001 minutes.
Physics question
- Thread starter Russinating
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Soldato
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but does the earth stop orbiting the sun from the moment of poof or 8.3 minutes later when we also lose the light?
ie what is the speed of gravity?
#deep
Soldato
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Hopefully there'll be no friction between you two? Best to let it slide.
i think this has caused a terminal rift between us
I remember those, I had a book of Autocar or some car magazine road tests with one in it, remarkable things
It is a shame they never quite made it into production.
But they got very close. The Rover P6 was the body that they planned to put the Gas turbine engine in as a separate production run to the piston versions. (Hence the unusual configuration for the front suspension)
I had a P6 2000TC at one time, they were smashing cars, I believe one of the best conceived and designed cars of all time. The attention to detail and consideration for making future repairs as easy as possible is really quite astonishing. I have actually worked in the Motor trade for nearly 40 years and I really have never seen anything remotely comparable! (I could make another post about this some time, perhaps in Motors) I am actually tempted to buy one if there are still any nice ones left that are available.
The main downsides the the GT were;
#1 Cost. The GT versions were twice the cost of the piston ones, which put them into the same price bracket as a standard family house (For the Millennials, you need to remember that back in the 60's, relative to other things. Cars were much more expensive than they are today and Houses were very much cheaper)
#2 Fuel consumption. Early versions were only good for 10MPG or so, though the later versions could manage 20+ which for a 150HP car in the 60's/Early 70's would not have been considered too excessive (Especially for a Luxury car).
#3 Surprisingly perhaps, no engine braking. If you took the foot off the gas, they just kept going. this had two consequences. Firstly, Drivers not used to this were badly spooked because they found it very difficult to control the cars speed, secondly, they absolutely ate brake pads! Unsurprisingly, the P6 was one of the first cars to have disk brakes all round. (Though, replacing the rear ones was always a complete ballache!)
AIUI The Rover GT cars and AC motors was one of the main reasons why the miserable bansturbaters in government introduced speed limits on Motorways.
Back in the day, the white lollipop with the black bar sinister meant "De-restricted" rather than NSL. On the motorways (And most other roads as-well outside urban areas) you could legally travel as fast as you liked/could, Subject, of course, to driving with due care and consideration and not driving dangerously and/or recklessly. How it should be today really!
But the civil service prodnoses got all ****** about Rover and AC Cars using the newly opened M1 as a test track for their prototype 150MPH motor cars.
And the rest, as they say, is History!
(
Soldato
****, what IS the speed of gravity?
Soldato
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Soldato
Not a concept I'd even considered before. Either way I think we'd all be dead within 8.4 minutes.come back when you've answered that and i'll give you a nobel prize
Soldato
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i dunno, wether the gravity ceases immediately or 8.3m later it's gonna take at least a day before the collapse of society, theoretically some people could survive for a very long time given our technology for self sustaining via alternate energy sources.
it does also raise the notion of life being possible on an exoplanet, after all what you need is energy and a molten core planet will have plenty of that sun or no sun.
Soldato
Ah right depends what you understand by the Sun going 'poooff', I assumed explosion but I guess makes more sense (and poses a more interesting question) to understand that as the Sun just ceasing to give off heat and light.
Since it is not possible for Matter/Mass to simply vanish, the question is moot.
(If the Sun went Nova, the mass would still be there, albeit spread out somewhat)However, The question as to how fast gravity "Travels" is actually a very interesting one.
What you are asking is how fast do ripples in space-time travel?
It seems to me (And I am not a theoretical physicist. Just somebody who fixes cars for a living) Is that those ripples travel at the speed of light, not because the speed of light is special, simply that light is a sort of ripple in spacetime and it can only travel as fast as other spacetime ripples can travel.
The speed of spacetime is the speed of spacetime. It is what it is!
There is no reason for it, it is just how our universe works (Or, perhaps, is made!
)
It is a shame they never quite made it into production.
But they got very close. The Rover P6 was the body that they planned to put the Gas turbine engine in as a separate production run to the piston versions. (Hence the unusual configuration for the front suspension)
.....
And the rest, as they say, is History!
What an interesting post. Never heard of these before.
Caporegime
@Orionaut someone built one you know. It's hilarious.
Any chance you could elaborate on your post? Preferably so it makes a modicum of sense
Soldato
I mean, IIRC TV is basically when the forces of gravity and drag even out, but in this case it's rolling not falling so its momentum is also aided by the centrifugal force involved?Any chance you could elaborate on your post? Preferably so it makes a modicum of sense
1. As well as gravity and drag (from both air resistance and friction in this casE), TV is affected by the buoyancy of an object (so in air it's very little, but still exists)
2. Where did you get the notion of centrifugal action for a coin rolling down a slope?
3. No such thing as centrifugal force, and there's certainly no centripetal force in this example.
This is coming from someone who probably thinks they know more than they actually do about physics (me not you).
Soldato
Soldato
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i suspect he's considering angular momentum to be a source of energy, but the thing is it's quite the reverse acting as a storage for energy, in his version it's the force of friction that adds to the angular momentum (assuming the centre of mass of the coin is in the centre of it's diameter).
of course friction is a result of the normal reaction force which will be the majority of the gravitational force that isn't the tiny amount that's accellerating the coin sideways.
if we really want to go into this i can go write out the full equation but i feel that's too much nerdery even for ocuk.
Permabanned
You'd be better brushing up on your grammar and punctuation, on complex subjects clarity is paramount, your post is unreadable
Soldato
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look, comma's, are, awesome, they, make, it, really, easy, for, you, to, avoid, proper, sentence, structure, and, in, the, bargain, annoy, people, on, the, internet,
Caporegime
Some pretty pro-click arguments in this thread. For bonus points:
JOHN has one sandwich which he cuts in half. How many sandwiches does JOHN have?
JOHN has one sandwich which he cuts in half. How many sandwiches does JOHN have?