Voltage and current in a resistor

AI Thread Summary
Voltage represents the potential energy due to an imbalance of charges, while current is the flow of those charges. In a resistor, the resistance does not draw current but instead impedes it, resulting in a voltage drop across the resistor proportional to its resistance, as described by Ohm's Law (V=IR). The term "voltage drop" refers to the energy lost as current flows through the resistor, which dissipates electrical energy. Understanding voltage as a measurable quantity involves recognizing it as the work done per unit charge, quantified in joules per coulomb. The discussion emphasizes the importance of grasping these fundamental concepts in electrical engineering for a deeper understanding of circuit behavior.
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Windadct said:
Sophie -not to be contrarian- IMO if the force applied is being equally reacted ( steady state as with drag / friction / resistance ) --- then the F applied = F reaction -- and work is done(power loss) . I agree to the inductor - this is the case where energy is stored in the system - inductors / capacitors... in these cases we are using Impedance - and we are talking about time varying cases - but regardless of the time - the Total force applied (Voltage) at any point in time is equal to the sum of each of the elements "reactive" force. ( really KVL right ?- the total sum =0, although the OP may ONLY see KVL as a mathematical tool - it is a (the) fundamental issue)
Consider a motor - not a resistor - looks like an inductor, then the back emf - is proportional to the mechanical force ( torque) and the power is the EMF ( Volts) * current... if there are resistors capacitors - what ever else in the circuit --- the back EMF becomes one of the SUM of forces - resisting the flow of current ( as I say pushing back).
This is my understanding - I do not consider this an analogy, but the fundamental principal. The same principal can be applied to many ( if not most) classical physical systems. Water in pipes, springs, gravity and friction blocs...

Either way round, it is not a good idea to try to equate Potential Difference (an Energy quantity) with Force. Using the right quantities and believing what the Maths delivers is usually the best way forward.
Volts are only allowed to be called a 'force' in the context of "emf", which is an ancient tradition and the term is used with fingers crossed.
 
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