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In a group of resistors connected in parallel, what is true of the voltage drop and the current through each resistor?
AThe current is the same through each resistor, but the voltage drop across each can differ
BBoth the voltage drop and the current are identical across every resistor
CThe voltage drop is the same across each resistor, but the current through each can differ
DNeither the voltage drop nor the current can be predicted for parallel resistors
Answer & Solution
Correct answer: C. The voltage drop is the same across each resistor, but the current through each can differ
1. In a parallel connection, both ends of every resistor are tied to the same two wires, one at the battery's positive terminal and one at its negative terminal.
2. Since each resistor spans the same two points, each sees the same voltage drop, equal to the battery voltage.
3. Applying Ohm's law separately to each resistor, I = V/R, the shared V but differing R values give differing currents through each resistor.
4. This is the mirror image of the series trap: in series the current is shared and voltage differs, while in parallel the voltage is shared and current differs.
5. The option claiming current is shared while voltage differs describes series resistors, not parallel ones.
6. The option claiming both quantities are identical everywhere ignores that different resistances draw different currents at the same voltage.
7. So the correct statement is that voltage stays the same while current can differ across resistors in parallel.
_Source: OpenStax Physics (CC BY 4.0), Ch 19 "Electrical Circuits", section 19.3 Parallel Circuits_
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