Backstory: I’m a software engineer just getting into electronics and it seems that everything I’ve ever been told about electricity my whole life is a candy-coated lie. I can’t find consistent logical answers to the most basic of questions and it’s driving me mad!
The kindergarten math V = IR makes sense... unless accounting for conservation of energy, matter, and real laws of physics.
I’m old enough now. I just want to know the truth, even if it hurts.
The effect of voltage on current
- A resistor, led, and copper wire walk into a bar
- The bar tender serves a 9v battery to share
- The electric field is too weak to serve the led directly
- The copper wire volunteers to help direct the electric field
- The ampacity of the led is too low, so the resistor hops up on the bar in-line with the copper wire so the LED can get a drink
- Ohms Law is a lie, but the coulombs are absolutely intoxicating. All hell breaks loose and the resistor catches the whole bar on fire, burns it to the ground, everybody dies, and I lost five dollars.
No, wait, there was no fire, that was just my anger at how every explanation I read of this scenario is in direct contradiction to what I thought I knew about conservation of energy and matter.
Contradictions for which I'd like answers
If charge causes the electrical field, then why does the voltage drop across the resistor? The electrons didn’t just magic themselves away. Isn’t the charge the same?
If charge passing though the resistor causes the atoms to enter a lower energy state, thereby releasing IR photons that heat up the place... then where did the extra coulombs go each second?
How come 2x resistance makes my battery lasts (on the scale of) twice as long but at (on the scale of) 1/4 of the power?
If resistance slows the flow of current, shouldn't ALL of the current still be accounted for somewhere on the system? solved: many of the explanations I was reading made it sound as though resistors lowered the current (...from infinity?) by "burning off" the "extra" current, which made no sense and contradicted the idea that the current supply and current drain were equal (Kirchoff's Law, common sense). Hence, the oversimplification of some of what I was reading confused me greatly.
... either my understanding is way off or there’s a well kept secret that few people are sharing (or my Google fu is busted)