Energy can it last forever?

We all know that light refracts. We all know it refracts because it slows down when it enters a denser material but the question is how does it speed up.Also do permanet magnets ever run out of magnetism, if not why are scientists ignoring this. I read about this on a serious science website but it was so long ago i can't remember the address. I'll search for it and if i find it i'll post it.

Also on the website was the fact that small amounts of energy (very small)can be created from nothing if they are required and only if it is returned almost instantly. So if these prove to be true does that mean a perpetual motion machine can be built?

These so called permanent magnets aren't really permanent, they lost their magnetism little by little (hundred years), I think metal alloy is one of the biggest factors.
They're just called permanent because they aren't like electric magnets which can be turned on and off.


Looks like our universum is open so in the end energy is all that will be left.

"Perm" magnets are not perm nor are they natural. What exactly are you asking regarding the perpetual motion machine?

Some body
www.phact.org...

There are many links to people claiming to have created a perpetual motion machine which puts out more energy than put in.

I ve always wondered about energy. 1 question i asked my science teacher was why a battery runs out of energy. She said because when the energy is used it transforms into another type of energy. I then wondered how come they couldnt just build two engines, 1 would gather energy from the original battery and the other would work on the conveted energy, then they could repeat it on and on giving the converted energy back and forth. Is this possible or am i wrong?

It works in theory, however with every time the first engine would work to transfere energy to the other engine, heat energy would be lost. This is why there is a lot of work going into finding ways in reducing heat loss.

Energy is said to never be able to be created or destroyed, how do they know this ? and I wonder if one day it will be proven to be wrong ?

If energy cant be created then how do i get more energy after i am tired from running

To answer your topic question, energy will last forever, Solar Energy that is. But we'll have to move into space to create big enough @fields@ to make any good amount of energy, and for it to be sent back to Earth.

We are running our of fossil fuels how ever, and these will probally disapear in the next 50 years or so, so we need to move to solar quite quickly...

Originally posted by Croat69
If energy cant be created then how do i get more energy after i am tired from running

If you didn't eat, drink water, or store energy that would be a big mystery wouldn't it? Certainly one that a grade school science class wouldn't be able to figure out, but they have long ago.

Originally posted by Nexus
To answer your topic question, energy will last forever, Solar Energy that is.

Even solar energy will not last forever all the suns will in time go out and in a really long time no new stars will be made to replace them. Every star in the universe will run down and cease to give light.

This will not happen for a something like trillions of years but it will happen leaving only black holes in the universe eating whatever is left.

[edit on 24-11-2004 by ShadowXIX]

most of the questions have already been answered, but i suggest you all look at this wikipedia site.
en.wikipedia.org...

the Kardashev scale is a scale defining civilization based on the amount of energy the civ can harness. infinite energy comes down the line around type VI (control over multiple universes) and type VII (deity).

infinite energy, as we know it, is not a possibility. the conservation of energy is the strongest of all the conservation laws, and thats saying something. it has come under a lot of scrutiny because energy can exist in many, many different forms. kinetic, potential, heat, sound, light, things we havent even discovered yet. here is no perfect system because there is always some, small loss to surroundings as real life is in no way ideal.

Energy lost during a conversion, eg: chemical to electrical in the case of a battery, is lost as another form of energy, ie: heat. I dont believe energy "lost" persay, but converted into multiple forms.

Originally posted by Iknowthelies
We all know that light refracts. We all know it refracts because it slows down when it enters a denser material but the question is how does it speed up.Also do permanet magnets ever run out of magnetism, if not why are scientists ignoring this.

The photons themselves don't slow down. They just interact with the medium and this makes it seem like the light is moving slower when viewed on a macroscopic scale.

The best possible engine that converts heat into motion is a Carnot heat engine.

Originally posted by amantine
The best possible engine that converts heat into motion is a Carnot heat engine.

damn straight. we did carnot two weeks ago in school, fascinating stuff. although, i will say, the wiki article is a severe bastardization of the process.

Originally posted by amantine

Originally posted by Iknowthelies
We all know that light refracts. We all know it refracts because it slows down when it enters a denser material but the question is how does it speed up.Also do permanet magnets ever run out of magnetism, if not why are scientists ignoring this.

The photons themselves don't slow down. They just interact with the medium and this makes it seem like the light is moving slower when viewed on a macroscopic scale.

The best possible engine that converts heat into motion is a Carnot heat engine.

I not sayimg your lying but some people have made light come to a complete stop or is this something different

Originally posted by Iknowthelies
I not sayimg your lying but some people have made light come to a complete stop or is this something different

light can be slowed if you pass it through supercold media, i believe. theyve slowed it down to what is by any other means a standstill, but its still technically moving.

Originally posted by Croat69
If energy cant be created then how do i get more energy after i am tired from running

You're not creating energy in this instance. What happens is your body converts energy from the oxygen you breathe in, the food you eat, and the liquids you drink, into a form of energy your body can use.

Is it true that energy can be borrowed from nothing as long as it is returned.

ome people say this explains the big bang in that the energy to create the universe was "borrowed" from nothing and so must be returned at the end of the universe.

If i'm talking bull someone stop me now please.