A student traverses a closed loop and adds all voltage rises and drops with proper signs. If the final sum is not zero, what is the most likely conclusion?
AKirchhoff's Voltage Law fails for all circuits
BThe student has made a sign or term error in writing the loop equation
CThe circuit has no source
DResistance becomes negative in the loop
Answer & Solution
Correct answer: B. The student has made a sign or term error in writing the loop equation
For a closed loop, KVL requires the algebraic sum of potential changes to be zero. A nonzero result in such a basic loop usually indicates a wrong sign convention, missed element, or algebraic mistake rather than failure of the law.
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