Why does the power consumption change as the voltage changes

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Scientific ideas please~

Power = volts x current.

For a specific resistance, as the voltage increases, electron current increases, and since power in Watts is equal to the voltage in Volts multiplied by the current in Amps, power is increased.

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That was a bit rude, I wasn't going to say that at all.

you have 3 values

resistance of component stays the same / fixed value

because resistance stays the same, as one of the other values decreases (eg voltage), the last value must increase (current)


Ohm's law.

When you measure voltage, you're looking at TWO different points on the circuit and measuring a force called EMF (electromotive force) between them. It moves from a higher potential (positive) to a lower potential (negative). You have to measure two different points to measure voltage.

To measure current, you are looking at ONE point and measuring how many electrons move past that point in a second.

Those are the individual components of the power equation.

Ohms law does not always hold.

It is not a fundamental law connected with underlying conservation laws.

See http://physicsnet.co.uk/gcse-physics/non-ohmic-devices/

ruveyn

Indeed. Especially with something metallic like the filament in a light bulb; the resistance will vary depending on the temperature of the filament. With some materials the resistance decreases with temperature with others it increases and with yet others it has a complex relationship with temperature.

Is this in reference to undervolting a specific CPU? I see the Linux penguin and was curious lol

i was speaking about a theoretical circuit with a linear resistance because nothing else was specified in the thread question.

i meant that in the context of explaining the voltage/current/resistance equation, using a constant R would help explain the relationship between V and I.

also, i think iv just got confused between one value going up and the other going down - i get really confused with this kind of thing.... ill have to go think about it for a while....