Difficulty: Easy
Correct Answer: Incorrect — the same current flows through every series element
Explanation:
Introduction / Context:Students often confuse rules for series and parallel networks. In a single-path series circuit, current does not split; thus, “adding currents” has no meaning because there is only one current everywhere in the loop. Recognizing this prevents calculation errors and misinterpretation of ammeter readings.
Given Data / Assumptions:
Concept / Approach:By definition, series elements carry identical current. KCL at each internal node implies current entering equals current leaving; with no branching nodes, the same current traverses all components. Therefore, the total current drawn from the source is simply that one current value, obtained via I = V_source / R_total for resistive networks, not a sum of separate branch currents (as would be the case for parallel networks).
Step-by-Step Solution:
Compute equivalent resistance: R_total = ΣRi for series resistors.Apply Ohm’s law: I = V_source / R_total.Recognize that this I is the same through each resistor: I1 = I2 = … = I.Conclude there is no summation of currents in series; there is only one current.Verification / Alternative check:Insert an ammeter at different series points; readings are identical, confirming that current is not distributed among branches but remains singular in magnitude and direction (for DC).
Why Other Options Are Wrong:
“Add the currents”: applies to parallel branches, not to a single series path.Frequency, value equality, or capacitors do not change the series current principle for the same instantaneous current in each element.Common Pitfalls:Confusing series and parallel behaviors; overlooking small leakage or measurement branches that can create unintended parallel paths.
Final Answer:Incorrect — the same current flows through every series element
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