Can Increasing Amperage Generate Arbitrarily Large Power with a Hand Generator?

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Discussion Overview

The discussion revolves around the capabilities and limitations of hand generators in producing electrical power, particularly focusing on the relationship between amperage, resistance, and power output. Participants explore theoretical scenarios involving high resistance and the physical constraints of human strength in generating power.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant suggests that using a hand crank generator to produce 1 amp with a 200 ohm resistor could theoretically yield 200 watts of power, raising questions about the potential for generating arbitrarily large power.
  • Another participant agrees with the possibility of generating high power levels if sufficient physical strength is applied, humorously questioning the feasibility of such strength.
  • It is noted that producing high power would require an equivalent amount of work from the user, emphasizing the physical limitations of the human body when cranking the generator.
  • A participant points out that using a very high resistance, such as 1MΩ, would result in an impractically high voltage, which the generator may not be able to handle, potentially leading to damage.
  • Concerns are raised about the wattage ratings of resistors, with an example given that a common 1/4 watt resistor would be inadequate for high power scenarios, suggesting the need for specialized components.
  • Discussion includes the mechanical limits of the generator and the user, questioning whether one could physically turn a generator producing extreme power levels.

Areas of Agreement / Disagreement

Participants express a range of views on the theoretical aspects of power generation with hand generators, with no consensus reached on the feasibility of producing arbitrarily large power or the practical limits involved.

Contextual Notes

Participants highlight limitations related to physical strength, resistor ratings, and the voltage capabilities of hand generators, but do not resolve these issues definitively.

tdammon
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Hi, I am a bit confused about what exactly is being produced when someone uses a hand generator. I know P=R(I^2). Does this mean that if I have a hand crank that can produce 1 amp I can use a 200 ohm resistor and produce 200 watts of power. If this is the case it seems as though producing any amperage can generate an arbitrarily large amount of power.
 
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tdammon said:
Hi, I am a bit confused about what exactly is being produced when someone uses a hand generator. I know P=R(I^2). Does this mean that if I have a hand crank that can produce 1 amp I can use a 200 ohm resistor and produce 200 watts of power.

Yes

If this is the case it seems as though producing any amperage can generate an arbitrarily large amount of power.

Yeah, if you were strong enough and the generator could handle in, you could produce thousands of horsepower just by turning the crank. Do you reckon you're strong enough? Good luck with that.
 
Sounds about right. But of course to produce that arbitrarily high power will require an even higher amount of power from your hand doing the cranking. You will always be limited by the power of your physique. As the resistance is increased the difficulty in turning the crank and maintaining 1 amp will get harder and harder.
 
You might be able to produce 200 Watts of power - by supplying at least 200 Watts or work to the crank.
Of course, you going to need a good size resistor to dissipate 200 Watts.

Then you figure that with a 1MΩ resistor you'll still be able to force 1 amp through.

If you do, the voltage will be V = RI = 1 million volts. Your hand crank generator probably can't handle that voltage. It will just arc over and start to damage itself.

But you can get one that will hold up. So now we'll choose the resistor.
A common resistor size is 1/4 Watts. For this experiment, that resistor would simply vaporize.
The wattage you are looking to generate is P = R(I^2) = 1 Tera watt.
So you will need to do one of two things, either find a 1 TW resistor or only run the experiment for a few picoseconds.

Now we need to talk about your arm and the mechanical limits of your generator. Are you up to turning that generator with 1TW of power (assuming no Kryptonite).
 

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