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electricty 1
- Thread starter imok2
- Start date
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- #42
To all of you that have participated in this discussion, Thank you. I would like to draw your attention to this web site, the source of all of my questions. I found this so interesting so I thought I would ask (pose) some of his questions. The author is Mr. William Beaty an Electrical Engineer and I think you should give it a look. I am not an Engineer,but I teach HVACR at a community college
SidiropoulosM
Electrical
imok2, after a quick first reading of Beaty's article I think this man likes to play with words and semantic twists and ends up making some absurd statements.
For example, he says:
"Electricity is made of electrons, while electrical energy is electromagnetism and is made of photons".
We all know that:
1. the presence of current and voltage means that we have electrical power.
2. if we have electrical power for some time, even a fraction of a second, we have electrical energy. Or, in mathematical terms, electrical energy is the time integral of power, which is the product of current times voltage.
3. photons have nothing to do with any of the above.
There are many more absurdities in the article but that's for another day.
To those espousing that "energy has no mass", I wouldn't quite agree. There is a clear physical relationship between energy and mass, evidence particle accelerators or cosmic rays. ( one astronomer recently detected a single elementry particle entering the upper atmsophere so fast it carried mass equivalent to a brick. They still cant find where specifically it came from. ) In particle physics the unit of energy is the electron-volt which is the amount of energy aquired by one electron accelerated by one volt. But when the "EV's" get high the "mass" of the energy quickly becomes apparent, vis. the large diameters of modern particle accelerators. The magnets which turn the particles about the circle cant turn particles above a certain energy, so they need to increase the size of the circles and the power of the magnets, eg. CERN's new accelerator. Effectively with added "acceleration" (energy input) above certain speed near c, velocity stops increasing and mass begins to increase, proving their interchangeability.
At the energies of these particles, all boundaries blur, e.g kg and/or volts and/or seconds etc. can be applied interchangeably to some measurements. (Someone at the start was asking about gravity. They havn't quite figured out how to get gravity to fit in interchangeably yet. I wouldn't agree that all energy comes from the sun, though that is a useful analogy if you prefix "useful forms on earth except fission, fusion, some chemical (e.g. pure hydrogen atoms arriving from another star as cosmic rays and reacting with oxygen to produce heat and water) and gravitation so far"
To get back to the question, I like the "water in pipe" analogy for electricity. Electron particle accelerators are almost a pure version of this, a pure example of DC current. And if you push some more water in one end of an inflexible pipe, you'll get water out the other end much faster than the water molecules individually travel. DC is similar, a wire is just a full pipe that doesn't naturally drain. AC is like heating a pipe loop on the other side of a wall by pumping small amounts "alternately" into each end of the loop very fast and waiting for the friction between the water and the pipe wall to heat up the pipe.
I know, that AC analogy sucks. Oh well.
At the energies of these particles, all boundaries blur, e.g kg and/or volts and/or seconds etc. can be applied interchangeably to some measurements. (Someone at the start was asking about gravity. They havn't quite figured out how to get gravity to fit in interchangeably yet. I wouldn't agree that all energy comes from the sun, though that is a useful analogy if you prefix "useful forms on earth except fission, fusion, some chemical (e.g. pure hydrogen atoms arriving from another star as cosmic rays and reacting with oxygen to produce heat and water) and gravitation so far"
To get back to the question, I like the "water in pipe" analogy for electricity. Electron particle accelerators are almost a pure version of this, a pure example of DC current. And if you push some more water in one end of an inflexible pipe, you'll get water out the other end much faster than the water molecules individually travel. DC is similar, a wire is just a full pipe that doesn't naturally drain. AC is like heating a pipe loop on the other side of a wall by pumping small amounts "alternately" into each end of the loop very fast and waiting for the friction between the water and the pipe wall to heat up the pipe.
I know, that AC analogy sucks. Oh well.
Skogsgurra
Electrical
Electricity is made up of electrons?
Rubbish!
As everyone knows: electricity is made of smoke.
Power stations make smoke, pump it through tiny pipes to your house or factory, into your machines where it makes them work.
Then it goes back along a second pipe to the power station and up the chimney, which we've all seen happen.
Don't believe me?
Well, what happens when the smoke escapes from inside the machine?
It stops working.
That proves it!
Sorry!
Carry on the discussion...
"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams
Rubbish!
As everyone knows: electricity is made of smoke.
Power stations make smoke, pump it through tiny pipes to your house or factory, into your machines where it makes them work.
Then it goes back along a second pipe to the power station and up the chimney, which we've all seen happen.
Don't believe me?
Well, what happens when the smoke escapes from inside the machine?
It stops working.
That proves it!
Sorry!
Carry on the discussion...
"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams
Skogsgurra
Electrical
RobWard,
I strongly disagree with your last posting. The smoke does NOT go to the homes through wires. The smoke goes up the smoke-stacks. You can see that clearly if you look at fossile fuel power stations. I do not know what happens to the smoke in nuclear plants, though. Anyone got a good explanation to that?
I strongly disagree with your last posting. The smoke does NOT go to the homes through wires. The smoke goes up the smoke-stacks. You can see that clearly if you look at fossile fuel power stations. I do not know what happens to the smoke in nuclear plants, though. Anyone got a good explanation to that?
May I have a try at this:
"Is this a true statement": Electric current is a flow of energy. Is energy and electricity the same thing?
Current (Amps) in electricity, is like gallons (or litres) in water. It is a quantity.
For the quantity to become power it must have some sort of force applied. In electrical terms this force is Voltage.
At any given instant of time the voltage applied to a completed circuit will push the current through that circuit delivering POWER to the circuit. If the circuit has a device in it such as a 60 Watt light bulb then the circuit will require the force VOLTAGE (usually fixed (ie 120 volts)) pushing the current AMPS (variable depending on the devices) through it. The product of the Voltage and the Current is power measured in WATTS. Power is an instantaneous value applied to a completed circuit. If the power is applied continuously over a period of time then energy is consumed. In electical terms this would be Watts x Time so that Energy = Volts x Amps x Time (usually hours) this produces Watts x Time or WattHours.
Now back to the question Is electric current a flow of energy. and the answer must be conditionally yes.
Is energy and electricity the same thing, and the answer must be conditionally yes.
"Is this a true statement": Electric current is a flow of energy. Is energy and electricity the same thing?
Current (Amps) in electricity, is like gallons (or litres) in water. It is a quantity.
For the quantity to become power it must have some sort of force applied. In electrical terms this force is Voltage.
At any given instant of time the voltage applied to a completed circuit will push the current through that circuit delivering POWER to the circuit. If the circuit has a device in it such as a 60 Watt light bulb then the circuit will require the force VOLTAGE (usually fixed (ie 120 volts)) pushing the current AMPS (variable depending on the devices) through it. The product of the Voltage and the Current is power measured in WATTS. Power is an instantaneous value applied to a completed circuit. If the power is applied continuously over a period of time then energy is consumed. In electical terms this would be Watts x Time so that Energy = Volts x Amps x Time (usually hours) this produces Watts x Time or WattHours.
Now back to the question Is electric current a flow of energy. and the answer must be conditionally yes.
Is energy and electricity the same thing, and the answer must be conditionally yes.
Skogsgurra
Electrical
I think that this discussion needs to be put back on track. So, here goes: Is ELECTRICTY (that is the name of this thread) the same thing as energy?
What do you suggest, jbartos?
What do you suggest, jbartos?
- Thread starter
- #54
I was wondering if this thread has had the most responses?
I will admit that sone of you are way above my intellect, but I enjoyed all of you very much.
P.S. I think I stick with HVACR, at least I think I know a little bit after 40 years in the business. Again thanks and I hope I can have other discussions with you all!!!
I will admit that sone of you are way above my intellect, but I enjoyed all of you very much.
P.S. I think I stick with HVACR, at least I think I know a little bit after 40 years in the business. Again thanks and I hope I can have other discussions with you all!!!
jbartos
Electrical
- Jan 15, 2000
- 6,440
Comment on alehman (Electrical) Oct 28, 2003 marked ///\\Just FYI, this is not a new topic.
///My postings and the energy versus mass relationships essentially agrees with
""Relativistic mass is equivalent to energy so it is a redundant concept. In the modern view mass is not equivalent to energy. It is just that part of the energy of a body which is not kinetic energy. Mass is independent of velocity whereas energy is not.
Let's try to phrase this another way. What is the meaning of the equation E=mc2? You can interpret it to mean that energy is the same thing as mass except for a conversion factor equal to the square of the speed of light. Then wherever there is mass there is energy and wherever there is energy there is mass. In that case photons have mass but we call it relativistic mass.""
Major shortcomings in some of these writings are missing dimensions pertaining to mathematical relationships covering engineering and science phenomena. Dimensions tackle the engineering and design mathematical relationships for all practical purposes.\\
///My postings and the energy versus mass relationships essentially agrees with
""Relativistic mass is equivalent to energy so it is a redundant concept. In the modern view mass is not equivalent to energy. It is just that part of the energy of a body which is not kinetic energy. Mass is independent of velocity whereas energy is not.
Let's try to phrase this another way. What is the meaning of the equation E=mc2? You can interpret it to mean that energy is the same thing as mass except for a conversion factor equal to the square of the speed of light. Then wherever there is mass there is energy and wherever there is energy there is mass. In that case photons have mass but we call it relativistic mass.""
Major shortcomings in some of these writings are missing dimensions pertaining to mathematical relationships covering engineering and science phenomena. Dimensions tackle the engineering and design mathematical relationships for all practical purposes.\\
jbartos
Electrical
- Jan 15, 2000
- 6,440
Suggestion: Reference:
1. Dwight E. Gray "American Institute of Physics Handbook," McGraw-Hill Book Company, 1972,
page 8-199 Table 8e-2 indicates:
MoC**2 in MeV
Photon Energy h(nu)o in MeV
Recoil Electron average energy (T)ave in MeV
etc.
Reference:
2. IEEE Std 100-2000 Dictionary
photon (1) (A) (fiber optics) A quantum of electromagnetic energy. The energy of a photon is h(nu) where h is Planck Constant [...h=6.626176(36) x 10**-34 kg m**2 s**-1 (or J s)] and nu is optical frequency.
1. Dwight E. Gray "American Institute of Physics Handbook," McGraw-Hill Book Company, 1972,
page 8-199 Table 8e-2 indicates:
MoC**2 in MeV
Photon Energy h(nu)o in MeV
Recoil Electron average energy (T)ave in MeV
etc.
Reference:
2. IEEE Std 100-2000 Dictionary
photon (1) (A) (fiber optics) A quantum of electromagnetic energy. The energy of a photon is h(nu) where h is Planck Constant [...h=6.626176(36) x 10**-34 kg m**2 s**-1 (or J s)] and nu is optical frequency.
SidiropoulosM wrote on 24th October,
'Question: is gravitational energy an exception? Is gravity a form of solar energy?'
Gravity appears because spacetime curves (or wraps), as per Einstein and this is the latest cause for the effect of gravity so far.
If the speed of gravity is equal to that of electromagnetic radiation, our belowed Earth would have fallen into Sun by this time (This is called Poynting-Robertson Effect). So gravity is otherthan electromagnetic radiation.
Jbartos may be correct in referring mass to energy (and viceversa) excepting gravity. A graviton is still a fictitious particle.
Thermodynamics says Electricity is a high grade energy (and heat is a low grade energy)
Regards,
Believe it or not : Had we trusted Archimedes and assigned him the work of lifting the earth(or any mass equivalent to that of earth on earth),with a lever of suitable length, it would have taken him 23 million million years to lift the earth by one centimeter.
'Question: is gravitational energy an exception? Is gravity a form of solar energy?'
Gravity appears because spacetime curves (or wraps), as per Einstein and this is the latest cause for the effect of gravity so far.
If the speed of gravity is equal to that of electromagnetic radiation, our belowed Earth would have fallen into Sun by this time (This is called Poynting-Robertson Effect). So gravity is otherthan electromagnetic radiation.
Jbartos may be correct in referring mass to energy (and viceversa) excepting gravity. A graviton is still a fictitious particle.
Thermodynamics says Electricity is a high grade energy (and heat is a low grade energy)
Regards,
Believe it or not : Had we trusted Archimedes and assigned him the work of lifting the earth(or any mass equivalent to that of earth on earth),with a lever of suitable length, it would have taken him 23 million million years to lift the earth by one centimeter.
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