Increase Voltage without Increasing Wattage?

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Discussion Overview

The discussion revolves around the possibility of increasing voltage without a corresponding increase in wattage, exploring the relationships between voltage, current, and power in electrical systems. Participants examine theoretical and practical implications, including the role of resistance and specific components like light bulbs and tunnel diodes.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants question whether it is possible to increase voltage without increasing wattage, suggesting that wattage must change if amperage remains constant.
  • One participant references Ohm's law, proposing that if resistance increases proportionally with voltage, wattage could remain unchanged.
  • A participant provides examples using light bulbs with different resistances to illustrate how changing voltage affects wattage under varying conditions.
  • Another participant mentions that ordinary resistors do not allow for an increase in voltage without an increase in wattage, but notes that tunnel diodes might have this capability.
  • There is a clarification about the definition of power as the rate of doing work, linking it to the concept of watts as joules per second.

Areas of Agreement / Disagreement

Participants express differing views on whether it is possible to increase voltage without increasing wattage, with some suggesting it is feasible under specific conditions while others argue that wattage will typically change with voltage. The discussion remains unresolved with multiple competing perspectives.

Contextual Notes

Participants reference Ohm's law and the behavior of different electrical components, indicating that the discussion is dependent on specific conditions such as resistance and the type of load. There are unresolved assumptions regarding the nature of the loads being discussed.

DB
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1. Is it possible to increase voltage without increasing wattage?

2. If 1. is yes, then is it more common that when voltage is increased wattage increases aswell?

Thanks
 
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DB said:
1. Is it possible to increase voltage without increasing wattage?

2. If 1. is yes, then is it more common that when voltage is increased wattage increases aswell?

Thanks

Power (in watts) = V * I

where V = voltage (volts), I = current (amps)
you should be able to figure out the answer from there
 
So then yes, the wattage must change (edit: with no change in amperage), thanks. But I have read (on wikipedia) that W=Joules per second or J/s ?
 
Last edited:
DB - remember ohm's law as well. E (voltage) = I (current) * R (resistance)

If you have a different load that has a resistance that is proportionally higher (by a square) of the voltage change than the wattage could remain the same.

But with the same load resistance, changing the voltage will have a direct effect on the wattage.

And if you change the voltage, the current will change too.

Quick example. I have a light bulb, it has a 240 ohm resistance.

If I apply 120V to it and .5A of current flows so therefore 60W of power is dissipated.

If I apply 60V to it and .25A of current flows so therefore 15W of power is dissipated.

Now I take a light bulb with a resistance of 960 ohms.

If I apply 120V to it and .125A of current flows so therefore 15W of power is dissipated.

Notice the last two examples have the same power but with very different voltages. And typically the source of power to use electricity comes from a power supply (like the wall outlet or some form from it) or battery so its called a voltage source. To change the power, you change the resistance. Light bulbs come in many ratings of power but its really just another way to describe the actual resistance of the filament in the bulb.

Cliff
 
As others state, to increase voltage without increasing (wattage) requires current to decrease when voltage increases. Ordinary resistors do not have this feature, but tunnel diodes do.
 
Thanks guys
 
DB said:
But I have read (on wikipedia) that W=Joules per second or J/s ?

Yeah, power is defined as the rate of doing work..
 

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