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Question
Choose the correct:
Four resistances 10 Ω, 10 Ω, 10 Ω and 15 Ω form a Wheatstone’s network. What shunt is required across 15 Ω resistor to balance the bridge
Options
10 Ω
15 Ω
20 Ω
30 Ω
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Solution
30 Ω
Explanation:
The below diagram represents Wheatstone’s network.
The Wheatstone’s network is said to be balanced when galvanometer shows null deflection. This occurs when:
`R_a/R_b = R_1/R_2`
Therefore the given configuration will be balanced when the equivalent resistance, after the shunt resistance Rs being added parallel to the 15 Ω and 10 Ω.
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