Increase Voltage without Increasing Wattage?

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Increasing voltage without increasing wattage is theoretically possible if the current decreases proportionally, particularly with specific components like tunnel diodes. However, in typical scenarios with standard resistive loads, increasing voltage will lead to an increase in wattage due to the relationship defined by the formula Power (W) = Voltage (V) x Current (I). For example, a light bulb with a higher resistance can maintain the same wattage at different voltages, but this is not common with ordinary resistors. Ultimately, changing the resistance is the primary method to alter power while adjusting voltage. Understanding these principles is crucial for effective electrical design and application.
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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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