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Suppose we use a 9V battery. Then the voltage between these two terminals is 9V. In other words, it would take 9 J of energy to move +1C of charge from the (+) to the (-) terminal by the electric field established by the battery.
So exactly how can electrical components "reduce" this voltage? How can we say that the potential difference between a resistor connected to a battery is 9V? This would obviously imply that the voltage would have to "move" in the circuit, such that right before the resistor, the potential is 9 V. Then after the current passes the resistor, the potential at this point immediately after the resistor, it is somehow 0 V. But this is wrong by definition, because it is +9V at the + terminal of the battery, and 0V at the - terminal of the battery.
I am confused?