Difficulty: Easy
Correct Answer: Incorrect
Explanation:
Introduction / Context:
Memorizing the right shortcut for identical components saves time. In series, resistances add. In parallel, conductances add, giving a very different shortcut for identical resistors that many students initially mix up.
Given Data / Assumptions:
Concept / Approach:
For identical parallel resistors: 1/R_eq = n * (1/R) so R_eq = R / n. The false statement claims R_eq = R * n, which is the series rule. Therefore, in parallel, the more identical branches you add, the smaller the equivalent resistance becomes, not larger.
Step-by-Step Solution:
Verification / Alternative check:
Example with R = 120 Ω and n = 3: R_eq = 120/3 = 40 Ω, clearly not 360 Ω. Bench tests confirm decreasing R_eq with added parallel branches.
Why Other Options Are Wrong:
Common Pitfalls:
Applying series addition to parallel networks; failing to switch to conductance thinking for parallel combinations.
Final Answer:
Incorrect
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