Sigh..please no long thread.

[Jimdandy]

 

Originally posted by Dingy:
LOL yes you are right....you can never go faster than the speed of light in a vacuum.  

But what if speed were relative...its measured by the time required to travel between two points.  If we were able to use gravitational forces to warp space-time thus bringing those two points closer together....
you can in essence travel the same distance in a shorter period of time.  Theoretically.

Ever watch Star Trek and their "warp" engines?  That is the physics premise warp drives work under...and to get you thinking even harder, physics does NOT disprove it.  The real limiting factor is the amount of gravitational forces required to warp space time enough to affect a ships travel    

Yer talking gravitational forces on the order of those generated by a black hole.

-Ding

I wasn't going to go into that on fscott because I'm sure he thinks I'm a real bag of wind already.   I love Star Trek. I think after all this brain teasing I need a cup of Earl Grey.  

"Damn it Jim I'm an engineer not an Astronomer!"  


[This message has been edited by Jimdandy (edited 01-30-2001).]

[fscott]

Jimdandy, thanks for your explanation.  I pretty much ignore any of the smartasses who tell me to go read a book and I appreciate your explanation. So, centripital force is the force which keeps the moon from accelerating faster and faster into the earth. I looked at the moon like a bullet shot out of a gun level with the earth. In one second that bullet will drop 32 feet, regardless of how fast it goes. And I know that if it goes fast enough it will miss the ground and go around the earth, What I was confused about was that since gravity was a constant, in 2 seconds the bullet would drop 64 feet, then 96 feet..I was wondering what kept it from eventually hitting the earth. So centriputal force. Ok. thanks.

fscott

[Jimdandy]

Your getting the idea fscott. Your more than welcome for the explanation. LOL I had to go get my book. It's been 10 years since I took physics so I'm rusty.     It's hard if you haven't taken trigonometry and drawn force diagrams to explain it on words. It does come down to the resultant centripetal force being equal to gravity. The bullet your describing will finally reach a point where the force pulling from gravity will balance with the KE of the bullet and slip it into a circular path around the earth. What you just describe is the Mercury rockets, the Space Shuttle or any satellite being launched into orbit. They are basically big bullets being fired into space. Now going belond placing an object in orbit and going to other plants can get real tricky. The only reason we were able to put a man on the moon was computers. We BARELY had the computing power to do it. The lunar lander had the approximate computing power of a Commodore 64. And the Commodore was more reliable. LOL! If you look at the formula as the radius of the orbit gets REAL big the gravitational force gets very small. Eventually it is so negligible as to be ignored. But it is always there. The whole universe is pulling on it self. That is why some people theorize that like the ball on the rubber band the universe will eventually stop expanding and start collapsing in on itself.

[This message has been edited by Jimdandy (edited 01-30-2001).]

[Dingy]

 

Originally posted by Jimdandy:
That is why some people theorize that like the ball on the rubber band the universe will eventually stop expanding and start collapsing in on itself.

LOL This is fun!  

Should we expound on this Jim?   There are two theorys here...the infinitely expanding universe and the expanding/contracting universal theory.  The big controversey is over the amount of matter in the universe.  If there is not enough matter in the universe to exert a gravitational pull to slow the expansion of the universe, the universe will continually expand and eventually burn out to a cold, energy-less cinder.

If, however, there is enough matter out there to eventually cease the expansion of our universe and cause it begin to contract, THEN we have an interesting situation.  Is the Big Bang a repeatable event?  Does the universe go through a cycle of big Bang/expansion/contraction/Big Bang?  

Right now, estimates on the amount of matter in the universe only account for about 60% of the required matter to cause the evntual contraction.  BUT....scientists are finding more and more hidden pockets of dark matter which add to the critical amount required to activate this Big Bang cycle.

Neat stuff eh?  

-Ding

[MrSiD]

I think the amount of roadkill on various BB's around the internet fills in conveniently the 'missing mass' needed for the universe to collapse.


- MrSiD

[Heater]

 

Originally posted by Hangtime:
How do I start the engine on the PT boat?

Hangtime That is simple RTFM  

------------------
!!! Heater !!!
 
Shit Happens All The Time

"If you have any trouble sounding condescending, find a UNIX user to show you how it's done."

[This message has been edited by Heater (edited 01-30-2001).]

[Jimdandy]

 

Originally posted by Dingy:
LOL This is fun!  

Should we expound on this Jim?   ...
-Ding

Ok.   I personally lean to the bang/contract because of the conservation of energy. But that assumes we are in a closed loop. We don't know what's outside the universe.   I've always like to contemplate what we were expanding into. If we are expanding that implies the is something to expand into. What is on the other side of that shock wave?   Is it like the age old question 'How many licks does it take to get to the tootsie roll center of a tootsie pop?'  

[Maverick]

Fscott,

If the moon falls onto the Earth, I hope it lands on you for starting this nonsense and for telling the moon it WAS falling.......  

Mav

[PakRat]

 

Originally posted by fscott:
Here's what i was getting at orginally. If you drop a ball in a vacuum with gravity being 10 ft/sec...that ball will be dropping at that rate.

Fundamental issue - 10 ft/sec is a speed - distance divided by time. Gravity has units of ft/sec^2 - it is an acceleration. The actual value is approximately 32 ft/sec^2 at the earth's surface.

Without the proper units, you ain't going to get anywhere.



------------------
Rape, pillage, then burn...

[Jigster]

10 ft/s is prolly meant to be the rounded form of 9.8 m/s^2  

I love how well the 10 fits into equations solved via the meteric system.

Meteric vs the US is so confusing sometimes...like mass = slugs

And the US system uses foot/pounds for torque, and the meteric system uses the same unit type but screws them up ... instead of meter/newtons (I still call them that anyway   ) vs newton/meters

Thank goodness for conversion tables.

- Da Bess

[Naso]

 

Originally posted by Dingy:
LOL yes you are right....you can never go faster than the speed of light in a vacuum.  

But what if speed were relative...its measured by the time required to travel between two points.  If we were able to use gravitational forces to warp space-time thus bringing those two points closer together....
you can in essence travel the same distance in a shorter period of time.  Theoretically.

Ever watch Star Trek and their "warp" engines?  That is the physics premise warp drives work under...and to get you thinking even harder, physics does NOT disprove it.  The real limiting factor is the amount of gravitational forces required to warp space time enough to affect a ships travel  

Yer talking gravitational forces on the order of those generated by a black hole.

-Ding

Yeah, the theory behind the warp-speed, actually is this, but the correct term is "curve" the space-time, or simpler, exit from it and cut a "shortroad" (? dunno word) out of the continuum.

BTW we already see a real application of this theory with planes warping everywhere.  

And yes, I like Star trek

"beam me up Scotty, there is no intelligent form of life on this planet"