In a balanced Wheatstone bridge network, the four arms have resistances , , , and . What is the value of the unknown resistance ?
Answer and explanation
Correct answer: C.
- Step 1: The condition for balance in a Wheatstone bridge is .
- Step 2: Rearrange to solve for : .
- Step 3: Substitute the given values: .
Answer
.
Why not the others: evaluates ; adds and ; and subtracts resistance values.
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