2007-12-18 18:36:19 · 12 answers · asked by Anonymous in Science & Mathematics ➔ Physics
people design and make things that run perpetually... but they take energy from somewhere to do it, and it's been going on for a long time
http://en.wikipedia.org/wiki/Atmos_clock
http://cgi.ebay.co.uk/1961-ART-DECO-JAEGER-LE-COULTRE-ATMOS-CLOCK-IN-ORIG-BOX_W0QQitemZ200184183826QQihZ010QQcategoryZ3931QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
you can buy your own lovely clock, that you wont have to wind or change the batteries. it takes the energy from the changing atmospheric pressure, which expands and contracts a piston or something, which winds the spring. just one example.
the physics-defying perpetual motion machine is not possible
as everyone has pointed out.
but then your answer depends if you take the literal meaning of 'perpetual motion', or what the term has come to mean...
2007-12-19 00:23:11 · answer #1 · answered by Anonymous · 0⤊ 1⤋
An object will continue in motion unless there are other forces acting on it. So, an object in space ( a probe for example) will continue spinning for a very very long time once the original 'spinning force' has been removed. In practise, space isn't a total vacuum, and energy will be lost by collision with minute debri and even atomic collisions. The process could take thousands of years - even millions! The earth is still spinning isn't it!
But when discussing perpetual motion, people often mean a device in which you can extract energy. Overbalancing wheels and other contraptions are put forward from time to time which claim that useful work can be extracted from them for ever.
Often, the devices are complex, requiring a continual source of energy in some form to keep going, but claiming to emit more energy than put in. Because the emitted and source energy is invariably light, heat, radiation etc - the energy accounting is experimentally difficult and then people claim that more energy came out than went in! But if they did the experiment 'properly' they would find that the perpetual motion machine is doomed to failure.....
2007-12-21 18:53:46 · answer #2 · answered by Mr Spock 2 · 0⤊ 1⤋
We ARE nearer to it through the application of so-called warm superconductivity. The us Navy has just completed testing of a large electric motor cooled with liquid nitrogen.
For more details go to
http://www.azom.com/details.asp?ArticleID=1276
In a sense perpetual motion has always been with us at an atomic level because of the partical movement which is perpetual.
2007-12-20 04:18:06 · answer #3 · answered by crazeygrazey 5 · 0⤊ 1⤋
Perpetual motion is not a matter of technology - it is fundamentally impossible according to the physical rules of the universe we live in. We will never have it.
That's not to say we won't have better, cheaper forms of energy in the future - but free perpetual motion is simply not possible.
2007-12-19 05:36:20 · answer #4 · answered by Daniel R 6 · 2⤊ 1⤋
My wifes mouth is in perpetual motion. God bless her
2007-12-19 02:43:15 · answer #5 · answered by Anonymous · 1⤊ 1⤋
Entropy - energy can neither be created nor destroyed it only changes its form.
So perpetual motion - NEVER.
RoyS
2007-12-19 05:37:42 · answer #6 · answered by Roy S 5 · 0⤊ 1⤋
It's impossible. Energy used is energy wasted. Not even the universe will last forever. Eventually there will be no more energy (heat, light -- "burning" stars) left.
2007-12-19 03:09:58 · answer #7 · answered by Lostfan108 1 · 0⤊ 1⤋
Perpetual motion was never possible nor will it ever be.
2007-12-19 02:41:43 · answer #8 · answered by gp4rts 7 · 2⤊ 2⤋
Hi
It's been around for years, you should see my ex mother in law, she never stops talking, her and her husband haven't argued in fifty years, it's not for the want of trying....he's just not quick enough to get a word in.
Ray. West York's. U.K.
2007-12-19 02:46:17 · answer #9 · answered by Anonymous · 1⤊ 1⤋
Only once we have worked out how to overcome friction and resistance.
2007-12-19 03:13:06 · answer #10 · answered by Anonymous · 0⤊ 0⤋