What really is "energy" -- is it the amps or the wattage?

In summary, volts is the "electro motive force" that pushes, while resistance tries to hold back. Amperage, or current, is the actual electricity, and watts is the calculation of everything together. In a vacuum, there would be infinite resistance, but in a superconductor, the current will not diminish due to resistance. The "power" is measured in watts, which is a measure of work being done. Voltage is like pressure and current is like flow. Both voltage and current can hurt, but the amount of energy they deliver depends on their relationship.
  • #1
VFEmitter
3
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If volts is only an "electro motive force", that is, it only pushes, and resistance is what tries to hold everything back, and "amperage", that is, current, is the actual electricity ( or not, that is my question ) and watts is the calculation of everything together and the total output, is it really just the amps that matter and the resistance and volts are just things in the way?

If you had zero resistance and just 2 volts and 10 Amps that means it is almost like infinite energy and it would spread in all areas that have zero resistance, like ina vacuum? It may sound like a stupid question, but I have been reading about electronics as a hobby for a while and I really don't understand the deep relationship between these three factors, resistance, voltage and amps besides Ohms law and such.
 
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  • #2
Wattage (joules/second) is a measure of work being done and is the product of the voltage across the load and the current through it. The voltage drives the current through the load, which causes the load to perform work, whatever that work may be.

Also a vacuum would have infinite resistance (no electrical connection whatsoever) rather than zero resistance. You're describing a superconductor. Ohm's law would be essentially irrelevant if the resistance was infinite since Ohm's Law only applies to an actual circuit, and you can't complete a circuit through infinite resistance.

Also there is no such thing as "infinite energy". In a superconductor, the current will not diminish due to resistance (at least not by any significant amount in a significant amount of time; yes I know these are non-exact terms and I apologize), but the energy in the circuit will never exceed that which you put into it.
 
  • #3
Thanks for enlightening me about the electrical resistance in vacuum, though load and work are relative terms, but still...

I have read somewhere that for example in an ocurrence of a static electricity phenomenon, it is the amps that hurt and not the volts, so while 10 volts and 3000mA and 1000 Volts and 30 mA have the same wattage, if you are hit by 10V x 3A you wouldn't survive, but it will be harder for that to happen because of the lesser voltage, and 1000 volts with 0.03 A will likely shock easily but it will only result in a minor injury each time, so, to me it seems like current ( amps ) is the real "power" and calculating wattage is only a practice that is convenient when making circuits and considering each component.
 
  • #4
The "power" is the watts. Like XZ923, it is Joules/sec. Joules is an energy.

The amps is what kills you because that is a measure of charge carriers per time. Voltage is more a potential energy. It can kill you if it can deliver the current, but when your hair stands up after rubbing a balloon, obviously the high voltage isn't hurting you.

People on here hate water analogies, but if you think of volts as pressure and current as flow a lot of things make sense. A huge amount of water without any pressure (high amps, low volts) will drown you, but a rain drop (falls from a great height, but very little flow) doesn't hurt you.

Don't get mixed up yet with terms like "energy". It has a specific meaning. In electrical terms, an energy of 1 Joule is a One Coulomb capacitor charged up to one volt. You can calculate how many electrons that is.
 
  • #5
Ok it makes sense now, I have now cleared the confusion, thanks to you both!​
 
  • #6
VFEmitter said:
Thanks for enlightening me about the electrical resistance in vacuum, though load and work are relative terms, but still...

I have read somewhere that for example in an ocurrence of a static electricity phenomenon, it is the amps that hurt and not the volts, so while 10 volts and 3000mA and 1000 Volts and 30 mA have the same wattage, if you are hit by 10V x 3A you wouldn't survive, but it will be harder for that to happen because of the lesser voltage, and 1000 volts with 0.03 A will likely shock easily but it will only result in a minor injury each time, so, to me it seems like current ( amps ) is the real "power" and calculating wattage is only a practice that is convenient when making circuits and considering each component.

Technically they both hurt; one doesn't exist without the other. To use a somewhat morbid analogy, imagine a boulder perched on the edge of a cliff. It has potential energy but as long as it's not moving there's no kinetic energy. If the boulder gets pushed off the cliff and you're under it, it will hurt, the same way an electric shock will hurt (or kill). The boulder is what physically hits you; gravity is the force causing it to hit you. With electricity, amperage is the measure of the actual current, voltage is the force driving it.
 
  • #7
VFEmitter said:
if you are hit by 10V x 3A
Impossible. The human body will not draw anywhere NEAR 3amps at 10v. In fact it will draw so little you won't even feel it unless you are using your tongue on the voltage terminals.

1000 volts with 0.03 A will likely shock
I'm not positive but I'm pretty sure that would kill you. Again, you don't get "hit with 1000 volts at 30 milliamps", you get hit with 1000 volts and your body will draw whatever current is appropriate for its resistance. I think that at 1000 volts, even if the supply is limited to 30milliamps, it would kill you.
 
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  • #8
VFEmitter said:
so while 10 volts and 3000mA and 1000 Volts and 30 mA have the same wattage, if you are hit by 10V x 3A you wouldn't survive, but it will be harder for that to happen because of the lesser voltage, and 1000 volts with 0.03 A

Phinds answered your comment correctly

you have the same misunderstanding that so many posting on here do
consider a 12V car battery, capable of supplying 300A + and you can touch both terminals and not feel a thing

it is the resistance of the load ... you or other circuit and the voltage across that load that determines the current that flows
this is regardless of if the power supply can supply 10A or 1000ADave
 
  • #9
VFEmitter said:
If volts is only an "electro motive force", that is, it only pushes,
EMF tells you how concentrated the energy is in a given amount of electricity.
The force that does the pushing is electrostatic force.
VFEmitter said:
..."amperage", that is, current, is the actual electricity (or not, that is my question)
Current is electricity in motion. Electricity itself arises from the surplus/deficit of charge.
XZ923 said:
Wattage (joules/second) is a measure of work being done
Or how fast work is being done.
 

1. What is the difference between amps and wattage when it comes to energy?

Amps and wattage are two different ways to measure energy, but they are not interchangeable. Amps, or amperage, measures the flow rate of electricity, while wattage measures the amount of power consumed by a device or system. In simpler terms, amps is the rate of energy flow, while wattage is the amount of energy being used at a given moment.

2. Which is more important in determining energy usage, amps or wattage?

Both amps and wattage play a role in determining energy usage. Amps determine the rate at which electricity is flowing, while wattage determines the amount of energy being used. Therefore, both are important factors in understanding the overall energy consumption of a device or system.

3. Can a device with low amps and high wattage be considered energy efficient?

Not necessarily. While a device with low amps may have a lower energy flow rate, the high wattage indicates that it is still using a significant amount of energy. Energy efficiency is determined by the amount of energy used to produce a desired output, so a high wattage device may still be considered energy efficient if it is able to produce a lot of output with a relatively low amount of energy consumption.

4. How does voltage play a role in understanding energy?

Voltage is another important factor in understanding energy. It measures the force or pressure of the electricity being used. In order for electricity to flow, there needs to be a difference in voltage between two points. Higher voltage typically means more energy is being used, but it is not the only factor to consider when understanding energy usage.

5. Is energy the same as power?

No, energy and power are not the same. Energy is the ability to do work, while power is the rate at which energy is being used. In other words, energy is the capacity to do something, while power is the measure of how quickly that capacity is being used. Wattage is a measure of power, while energy is typically measured in joules or kilowatt-hours.

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