Energy - Page 1
Forum section: electronics / general

author: texwitheffects
author_rank: Contributor
timestamp: November 01, 2015, 07:56:33 pm
content: So I heard that energy cannot be created or destroyed, but energy degrades into heat and is ruined down into forms of less availability. Like when you set it on fire it seems like it is gone forever. Is heat a form of energy? Or is heat the dying product of energy?Sent from my iPhone using Tapatalk

author: German_EE
author_rank: Super Contributor
timestamp: November 01, 2015, 08:21:08 pm
content: Heat is one form of energy and appears on the electromagnetic spectrum along with light. You are correct that (in theory) energy can never be created or destroyed but I'm wondering if that particular law was created before nuclear weapons became reality.I digress........................If you heat something to (say) 100C then remove the source of that heat the object that you have been heating will reduce in temperature until it equals the temperature of its surroundings. Heat always travels from a warm body to a cool one but none of this heat is ever lost. Your 100C object first heats the atmosphere around it and then the warmer atmosphere transfers some of THAT heat into the other objects in the room. If you have thin walls or uninsulated windows then some of the heat in your room will travel through and heat the air outside by a small degree.

author: Zero999
author_rank: Super Contributor
timestamp: November 01, 2015, 08:47:42 pm
content: Quote from: German_EE on November 01, 2015, 08:21:08 pmNuclear reactors still obey the first law when mass-energy equivalence is taken into account. Einstein's famous formula shows this E = mc2

author: Rick Law
author_rank: Super Contributor
timestamp: November 01, 2015, 09:49:22 pm
content: Quote from: Hero999 on November 01, 2015, 08:47:42 pmTo be more precise, mass and energy are one and the same. Mass is but another form of energy.That said, there is alwaysterminology problems. "Dark Matter" in astronomy refers to the unseen matter causing the yet unknown "additional" gravitational attraction that helps holding the galaxy together. Without that, there is not enough mass to hold the galaxy together. "Dark Energy" in astronomy on the other hand refers to the unknown energy that pushes the expansion of the universe. We know the universe is continuing to expand - and rate of expansion is accelerating. We don't know what causes it, and we just call that unknown factor the "dark energy".In astronomy, anything they don't see is "dark" something...

author: Zero999
author_rank: Super Contributor
timestamp: November 01, 2015, 11:40:45 pm
content: Quote from: Rick Law on November 01, 2015, 09:49:22 pmYes in any system where energy is lost to the surroundings the mass of the system will be reduced but it's only in highly energetic reactions such as nuclear reactors where this becomes actually measurable. In order for just 1mg of mass to be lost, 89.87GJ of energy would be transferred to the surroundings but this would be immeasurable reduction in mass in something like a li-ion battery which would need to be 150 tonnes to store that much energy. Of course no mass/energy would really be lost. It would just be transferred to the surroundings.

author: hamdi.tn
author_rank: Frequent Contributor
timestamp: November 01, 2015, 11:58:54 pm
content: Quote from: texwitheffects on November 01, 2015, 07:56:33 pmYes it is. As simple as that.We tend to consider heat as lost energy , cause it's undesirable effect on all electronic system. but it still a quantity of energy neither created nor destroyed it's only passing from one form to an other.for this whole universe considered as a closed system that can't exchange energy with any external system (if they exist) so it's energy conservator and can't lose or create energy.

author: tom66
author_rank: Super Contributor
timestamp: November 02, 2015, 12:28:28 am
content: All forms of energy ultimately end up as heat, and the point at which all temperatures at all points are equal is the point at which maximum entropy has been reached and the universe is "dead" (see: Heat Death of the Universe)

author: IanB
author_rank: Super Contributor
timestamp: November 02, 2015, 12:54:48 am
content: Quote from: texwitheffects on November 01, 2015, 07:56:33 pmSimplified, thermodynamics divides energy into two forms, Heat and Work. Heat is related to temperature, and work is everything else. Work is the useful kind of energy, since it can "do stuff". When electricity flows through an electronic circuit, it is doing work.When heat flows from a hot source to a colder sink then some of it can be converted into work, but not all of it. When you fuel your car with gasoline it burns in the cylinders and makes a lot of heat. Some of the heat makes the car go and the rest is lost out the exhaust pipe and radiator. It is impossible to use all the heat from the gasoline to make the car go--some heat must always be discharged to the surroundings. There is therefor a limit on how efficient an engine can be.Although you can turn high temperature heat into useful work, that work will eventually turn back into (less useful) low temperature heat. Energy is therefore always flowing downhill. Once you have used it you can't use it again. That is why we always have find new sources of energy to replace what has been used. We have to find new reserves of oil and gas, or find ways to use the energy from the sun (hydroelectric, wind, tidal, solar, ...).

author: texwitheffects
author_rank: Contributor
timestamp: November 02, 2015, 01:14:09 am
content: Quote from: hamdi.tn on November 01, 2015, 11:58:54 pmThis is a really cool thought.Sent from my iPhone using Tapatalk

author: texwitheffects
author_rank: Contributor
timestamp: November 02, 2015, 01:15:03 am
content: Quote from: IanB on November 02, 2015, 12:54:48 amSo you are saying that energy can be destroyed and that we need to look for more energy?Sent from my iPhone using Tapatalk

author: IanB
author_rank: Super Contributor
timestamp: November 02, 2015, 01:33:03 am
content: Quote from: texwitheffects on November 02, 2015, 01:15:03 amIt's not destroyed, it is simply no longer useful. So yes, we always need to look for more energy. You can't recycle it, you always need fresh supplies.

author: texwitheffects
author_rank: Contributor
timestamp: November 02, 2015, 01:38:13 am
content: Quote from: IanB on November 02, 2015, 01:33:03 amWell maybe we can find a way to reuse the un useable energy lolSent from my iPhone using Tapatalk

author: Delta
author_rank: Super Contributor
timestamp: November 02, 2015, 02:14:24 am
content: all energy comes from frequencies, and all frequencies are energy. there are plenty of frequencies to use for energy, but the big corporations don't want the public to know about them.

author: daqq
author_rank: Super Contributor
timestamp: November 02, 2015, 07:56:33 am
content: QuotePlease explain.

author: AndyC_772
author_rank: Super Contributor
timestamp: November 02, 2015, 08:29:31 am
content: Quote from: IanB on November 02, 2015, 12:54:48 am"Work" is a term almost exclusively used to mean mechanical work, equal to force * distance.When an electric current flows through a circuit, electrical energy is converted into heat energy. Unless the circuit includes a mechanical transducer, like a speaker or solenoid, there's nothing physically moving and therefore no "work" is done.Quote from: texwitheffects on November 02, 2015, 01:15:03 amNo, not destroyed. For all practical purposes, unless you're specifically building nuclear reactors or atomic weapons, energy can only ever be converted from one form to another, but the total energy in a closed system always remains the same.Saying that "we need to look for more energy" is more of a social / environmental comment than a scientific one. In scientific terms, fresh input of energy from outside is needed to keep a system (such as an electric motor, or computer, or internal combustion engine) operating, because the energy in that system has been converted into forms which are no longer useful. Usually, that form is waste heat.QuoteAbsolutely correct. One excellent example to study would be a combined heat and power plant, in which the heat from combustion is used to generate steam to drive a turbine and run a generator, and once it's cooled to the point of no longer being useful for electricity generation, it's directly distributed to customers who require it for heating.QuoteNo! Reusing heat that would otherwise be lost is perfectly good science!Quote from: Delta on November 02, 2015, 02:14:24 amTotal nonsense

author: hamdi.tn
author_rank: Frequent Contributor
timestamp: November 02, 2015, 08:45:05 am
content: Quote from: Delta on November 02, 2015, 02:14:24 amIn waves theory Frequency is only an other characteristic of waves among other (obviously amplitude of it's electric and magnetic component ). Now waves carry energy (that can depend of wave frequency too ) and we certainly using one of them on a daily basis - Solar energy.

author: G7PSK
author_rank: Super Contributor
timestamp: November 02, 2015, 09:07:22 am
content: Quote from: Delta on November 02, 2015, 02:14:24 amAll electromagnetic waves (frequencies) also exhibit particle properties (photon)

author: Mechanical Menace
author_rank: Super Contributor
timestamp: November 02, 2015, 09:28:51 am
content: Quote from: G7PSK on November 02, 2015, 09:07:22 amBosons are weird, while thinking of them as waves or particles is a useful abstraction and not necessarily true if you are going to think of them like that then they aren't waves that exhibit particle like properties or particles that exhibit wave like properties but both at the same time.I like to think of them as a high point in a field that just so happens to be able to propagate the field they manifest in. Well except for the Higgs boson which is a manifestation of a filed that already permeates everything so is extra weird lol

author: Delta
author_rank: Super Contributor
timestamp: November 02, 2015, 10:01:49 am
content: I've been getting really into frequencies, especially the ones the government and corporations don't want us to know about. As usual, all the mainstream so-called experts are quick to deny the frequencies of energy on here.https://www.eevblog.com/forum/chat/frequencies/

author: Mechanical Menace
author_rank: Super Contributor
timestamp: November 02, 2015, 10:08:26 am
content: Quote from: Delta on November 02, 2015, 10:01:49 amIf you've got a problem with the so-called experts opinions on the matter there's an easy fix, show them the evidence that backs up your hypothesis.

author: Delta
author_rank: Super Contributor
timestamp: November 02, 2015, 10:19:05 am
content: Quote from: Mechanical Menace on November 02, 2015, 10:08:26 amDid you click on my link? Lots of "fascinating" info there 😂

author: hamdi.tn
author_rank: Frequent Contributor
timestamp: November 02, 2015, 10:23:18 am
content: Quote from: Delta on November 02, 2015, 10:01:49 amman , really, there is nothing called frequencies of energy ... it's energy carried by waves with frequency.while your idea is quite true, you having a hard time explaining it, and conspiracy theory certainly doesn't help. cause as i said using energy of EM waves is all around you starting with your radio to your photoelectric panel.

author: Artlav
author_rank: Frequent Contributor
timestamp: November 02, 2015, 10:32:16 am
content: A common confusion is that the term "energy" can mean two things: something useful for doing work, and some "level" for lack of a better word.Imagine two situations.First, you are on Earth, and have a lot of hot air. 500*C hot.You have a source of energy - as that air cools, it can drive mechanical machines, or you can use peltier/termocouple devices to turn the heat to electricity, and so on.The hot air have energy, of the useful kind.Second, imagine that you are on Venus.You have the same supply of 500*C air all around you.However, there is no useful energy to be had, since all the air is equally hot around you.This is the energy of the "energy level" kind.There have to be a difference in energy levels for it to be useful. I.e. you can stick a radiator out into space from Venus, and that hot air would suddenly becomes useful.There is an energy level difference between a wound spring and an unwound one, between alcohol molecule and the water and CO2 ones it burns into, between 4 hydrogen atoms and one helium atom they can fuse into, and so on."Energy source" means something that would exhibit that difference.Oil and coal that can be burned into simpler molecules.Hydrogen that can be fused, or uranium that could be fissioned.Heat from the Earth interior, contrasted with the cold of it's surface.That's what "energy" mean.

author: Simon
author_rank: Unknown
timestamp: November 02, 2015, 12:34:02 pm
content: Quote from: Delta on November 02, 2015, 02:14:24 amWe don't need this bollocks on the forum, you have been wrned!

author: Galenbo
author_rank: Super Contributor
timestamp: November 02, 2015, 12:38:57 pm
content: So this "texwitheffects" guy is the same guy that wanted to talk about "frequencies" in this tread:https://www.eevblog.com/forum/chat/frequencies/75/and despite the claimQuote from: texwitheffects on August 16, 2015, 10:32:36 pmbumped upon his own limit to learn the absolute basics.and then concluded with this quote:Quote from: texwitheffects on August 16, 2015, 10:32:36 pmI think the dick drawer is back...

author: Delta
author_rank: Super Contributor
timestamp: November 02, 2015, 01:06:49 pm
content: Quote from: Simon on November 02, 2015, 12:34:02 pmGet a grip of yourself, Si! The OP is the one who's into all that kind of shite, I even linked to his last thread. Now he's trying to chat the same crap about "energy". I thought that if the noble mods are happy with him posting ludicrous nonsense, then I would join the fun too...

author: daqq
author_rank: Super Contributor
timestamp: November 02, 2015, 01:13:30 pm
content: Quote from: Delta on November 02, 2015, 10:01:49 amAh, bullshit. Thanks for the explanation.

author: Rick Law
author_rank: Super Contributor
timestamp: November 02, 2015, 05:02:00 pm
content: Quote from: tom66 on November 02, 2015, 12:28:28 amActually, heat death of the universe may not be an issue but rather death of the local region would be the issue.Since the expansion of the universe continues to accelerate, in the time scale of trillion-trillion years, the nearest galaxy (or even the nearest star) will be "receding" faster than the speed of light. The nearest star is not "moving away" faster than light, but the space between us and it expanded. When the added distance due to expansiondX/dT > cthey are receding faster than the speed of light.Once the dX/dT > c is reached, it is "receding" so fast the light it emits cannot get to us. So, when all the visible light or available energy within our region are gone, our "local universe" is dead.In many ways, we are lucky to live in this time frame. We have enough visible systems that we can deduce the original of the universe: big bang. It happened not so long ago that we can tests the big-bang theory by detecting the left over microwave.When most systems already receding faster than light, living beings then would not see super clusters galaxies. Some point later, they will not see super clusters but only the local cluster. Some point later, they will see only their own galaxy, then only their own local star cluster, then only their local star.At that point in time, they don't see enough to deduce how the universe started. The background microwave would long since disappear. Trillion-trillion years from now, folks will not know there are more stars out there. No dust cloud, and nothing to deduce how their sun was formed.

author: Simon
author_rank: Unknown
timestamp: November 02, 2015, 05:41:08 pm
content: Then don't feed the troll, just report it, the longer the thread goes on the longer it takes to sort things out. I often check in during lunch at work and sort out any reports before things get worse by the evening but I don't have time to read everything. As it happens YOUR post is the one that got reported.Quote from: Delta on November 02, 2015, 01:06:49 pm

author: Delta
author_rank: Super Contributor
timestamp: November 02, 2015, 05:57:56 pm
content: OK, fair enough mate. Sorry, I was just having a laugh, but I do appreciate it must be quite difficult keeping on top of crap like this.