For a balanced Wheatstone bridge with $P = 1.36\ k\Omega$, $R = 300\ \Omega$ and $S = 4.4\ k\Omega$, the unknown $Q$ is approximately:
A~5 kΩ
B~200 kΩ
C~19.94 kΩ
D~0.5 kΩ
Answer & Solution
Correct answer: C. ~19.94 kΩ
Balance: $P/Q = R/S$ ⇒ $Q = PS/R = (1.36\times10^3)(4.4\times10^3)/300 \approx 19.94\times10^3\ \Omega \approx 19.94$ kΩ.
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