# B Voltage and Current, why?

#### jbriggs444

That's an understandable mechanism for Dissipation of Power in a resistive conductor. However, the 'slope ' equivalent for along a low resistance supply wire is more or less horizontal / zero. That doesn't take care of Power Transfer to a resistive load.
Yes, you are absolutely correct. The two analogies address different aspects of the situation.

#### sophiecentaur

Gold Member
Yes, you are absolutely correct. The two analogies address different aspects of the situation.
A great example of a PF discussion where people take sides at the drop of a hat. (Mea culpa too)
Interestingly, if we consider two series resistors, one of them could be regarded as 'supplying Power' to the second in the chain. Dissipation in the supply Resistor can be modelled by KE to Thermal transfer and the transfer of Power through a resistor is a matter of Force times Distance (=Work).
I will leave it to the objectors to my idea to square it with the OP, if he/she is further confused by all this.

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#### David Lewis

In a circuit with a set resistance, let's say 1 ohm, the current flowing through the circuit is the same as the supply voltage.
It's numerically the same because of the units chosen. Current and voltage can never be the same because they are different quantities.
Treating the earth as an inertial frame in General Physics examples is a "misconception".
But it's not a model. It's a simplification. Nobody is fooled into thinking that, by ignoring gravity, it doesn't exist.

"Voltage and Current, why?"

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