Ask a physicist anything. (7)

[Wiccan_Child]

Well, a lot of them have that, too. Really depends upon what animal you're talking about.

Mesonychoteuthis hamiltoni. Discuss.

 

[Exiledoomsayer]

What are the methodes used in order to date uncovered traces of ancient towns?

 

[Nabobalis]

Mesonychoteuthis hamiltoni. Discuss.

Dinner time?

The animal kingdom is brilliant and quite scary too. The BBC has a brilliant range of TV shows recently on them (Frozen Planet, The Great Barrier Reef and Earthflight).

 

[Wiccan_Child]

Dinner time?

The animal kingdom is brilliant and quite scary too. The BBC has a brilliant range of TV shows recently on them (Frozen Planet, The Great Barrier Reef and Earthflight).

I'm watching the Great Barrier Reef as we speak! Spooky .

 

[TemperateSeaIsland]

if scientists are so clever why is the world in such a mess?

The Jews?

 

[Wiccan_Child]

What are the methodes used in order to date uncovered traces of ancient towns?

Human settlements are good in that they're unlikely to be older than 50,000-70,000 years, which means we can use good old-fashioned carbon dating. Calibration has to be performed as [sup]14[/sup]C levels are not constant - things which are 6000 years old are carbon-dated as 7000 years old, if uncalibrated.

Interestingly, radiocarbon dating hits a problem for things from between 400 and 800 BCE - we can't be more accurate that that. So, if something was made in 600 BCE, radiocarbon dating will only be able to say that it's true date is 800-400 BCE.

 

[acropolis]

Classic victim mentality. Blame every one else.

So scientists shouldn’t take any responsibility for the state of the world today?

Are scientists unwilling or just unable to make the world a better place.

Scientists are one of the few groups of people working to make the world a better place, they just don't have the power to do much. It's the politicians and generals and religious zealots that work tirelessly to drag with the world into more chaos and suffering.

 

[Zippy the Wonderslug]

How is it that when I turn on the water facet at home, there's pressure that shoots it all out.

Does this pressure come locally or is it from the water company?

Sorry for the dumb question this time.

 

[Chalnoth]

How is it that when I turn on the water facet at home, there's pressure that shoots it all out.

Does this pressure come locally or is it from the water company?

Sorry for the dumb question this time.

It's a combination. There are pumps spread throughout the water system that keep the pressure high enough that the water comes out. Friction in the lines means that you have to have pumps in different places, and if you live in a larger building, they will have to have pumps on the higher floors to keep the water flowing. Pumps are also obviously used to push the water uphill.

 

[acropolis]

Water towers are also used to provide water pressure. The water is pumped to the top where gravity provides the water pressure.

 

[Zippy the Wonderslug]

Thanks for the explanations.

 

[Chalnoth]

Water towers are also used to provide water pressure. The water is pumped to the top where gravity provides the water pressure.

Well, that's one way. It's not universally used.

 

[acropolis]

Well, that's one way. It's not universally used.

Certainly not. I'm curious why water towers wouldn't be used, however, since it seems like an elegant way to provide an even pressure even in the case of temporary power outages. The only city I've lived in that didn't use water towers had naturally occurring hills throughout the area, so they just built massive tank on those hills.

 

[Chalnoth]

Certainly not. I'm curious why water towers wouldn't be used, however, since it seems like an elegant way to provide an even pressure even in the case of temporary power outages. The only city I've lived in that didn't use water towers had naturally occurring hills throughout the area, so they just built massive tank on those hills.

My guess would simply be space requirements. But yes, elevated tanks are quite efficient forms of energy storage, allowing the water company to only pump water into the tanks when it's cheapest.

 

[Zippy the Wonderslug]

I once was watching a pastor on TV trying to explain the concept of time.

He did something weird.

He took the size of the universe and divided it by it's age and came up with 365, the same number of days we have in a year.

Anyone have a guess as to what theory this might be or was it most likely his own personal take on time?

 

[Wiccan_Child]

I once was watching a pastor on TV trying to explain the concept of time.

He did something weird.

He took the size of the universe and divided it by it's age and came up with 365, the same number of days we have in a year.

Anyone have a guess as to what theory this might be or was it most likely his own personal take on time?

It sounds like dodgy mathematics to me. What where his units? I can divide my weight by my height and get any number I want - provided I choose the correct units.

Moreover, there's the rather glaring flaw that we don't actually know how big the universe is. There is an observable horizon beyond which we can't see, because anything beyond that is too far away for its light to have reached us. I'd be interested in what figure he used for the size of the universe, as that would be another flaw in his argument right there.

 

[Zippy the Wonderslug]

It was something I saw like 10 years ago.

He was trying to explain the 6,000 years, historical account in the Bible.

His main point was on the perspective of the author.

So 6,000 years could be several billion depending on where you're observing Earth's history.

He said something like one could send out a constant beep, beep, beep signal.

When planet Y receives the first beep, it could be a 100 years before they heard the next one.

Other than that, I don't remember much, he was a little hard to follow. Sorry.

 

[Zippy the Wonderslug]

I think I found something on this.

Age of the Universe

I'll have to read it later since that page is a little too intensive for my tablet.

Can you poke any holes to this theory?

 

[pgp_protector]

Q: What's the best design for a Desktop Sized Trebuchet for a School Project?

 

[Chalnoth]

I think I found something on this.

Age of the Universe

I'll have to read it later since that page is a little too intensive for my tablet.

Can you poke any holes to this theory?

"The world may be young and old simultaneously" is just a bad use of language. Either it's young, or it's old, or you've redefined young to mean old in which case your statement as lost all meaning.

As the rest just seems like an exercise in talking about what people thought some thousand years ago or so, I just don't see the point in bothering with it. What people talked about back then is completely irrelevant to the nature of reality. The world simply doesn't care what we humans talk about.