I'm a little confused about the relationship between voltage, current and resistance. I do know V=IR; but as to the relationship between voltage and current- (holding resistance to be constant) does a change in voltage cause a change in current or is it a change in current causing a change in voltage? I might not even be understanding current and voltage properly I don't even know
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3$\begingroup$ I'm voting to close this question as off-topic because of lack of elementary research. $\endgroup$– ZeroTheHeroCommented Oct 27, 2019 at 0:31
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2 Answers
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Which is the cause and which is the effect is irrelevant. There is a linear relationship between them (at least when only resistors are involved), and that is what is important in analyzing circuits.
However, from the standpoint of fundamental physics, a difference in electrical potential (voltage) causes charge to flow (current) if it can flow. Flowing charges do not necessarily cause a difference in electrical potential. So you should think of voltage as the cause and current as the effect.
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No. A current through a resistor can & does produce a voltage drop. As charges move through a resistor, they collide with lattice ions. When an electron collides with an ion, it can drop from conductance band down to valence. This is a drop in energy state since the valence band is a lower energy state than conduction band, ie more negative. As a result, the lattice ion gains an electron, becomes more negatively charged, & a photon is emitted to conserve energy. The resistor feels warm as it radiates heat due to conduction. Clearly the voltage drop across the resistor is a result of charge flow through it, ie current. But if a resistor is connected directly across a CVS, constant voltage source, then the current is determined by V/R. Either one, I or V, can be the independent quantity, the other being dependent. V=IR, is a functional relation, not causal, since either one can cause the other.
Claude Abraham