Increase Voltage without Increasing Wattage?

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    Voltage Wattage
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SUMMARY

It is not possible to increase voltage without affecting wattage when using ordinary resistors, as power (in watts) is calculated using the formula Power = Voltage (V) * Current (I). If the resistance remains constant, an increase in voltage results in an increase in wattage. However, under specific conditions with different loads, such as using tunnel diodes, it is feasible to increase voltage while maintaining the same wattage by decreasing current. This discussion highlights the relationship between voltage, current, and resistance in electrical systems.

PREREQUISITES
  • Understanding of Ohm's Law (E = I * R)
  • Familiarity with electrical power calculations (Power = V * I)
  • Knowledge of resistance and its impact on electrical circuits
  • Basic concepts of voltage sources and load characteristics
NEXT STEPS
  • Research the properties and applications of tunnel diodes in electrical circuits
  • Explore advanced concepts in electrical engineering related to power management
  • Learn about different types of resistors and their behavior under varying voltage conditions
  • Investigate practical applications of voltage regulation in power supply systems
USEFUL FOR

Electrical engineers, physics students, and anyone interested in understanding the principles of voltage, current, and resistance in electrical systems.

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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