Question: If the resistances in a Wheatstone bridge are R1 = 10Ω, R2 = 15Ω, R3 = 5Ω, what is the value of R4 for the bridge to be balanced?
Options:
Correct Answer: 12.5Ω
Solution:
Using the balance condition R1/R2 = R3/R4, we have 10/15 = 5/R4. Solving gives R4 = 7.5Ω.