In the shown arrangement of the meter bridge AC corresponding to null deflection of galvanometer is x. What would be its value if the radius of the wire AB is doubled?
In the shown arrangement of the meter bridge AC corresponding to null deflection of galvanometer is x. What would be its value if the radius of the wire AB is doubled?
Show Hint
- \(x\)
- \(x/4\)
- \(4x\)
- 2x
The Correct Option is B
Solution and Explanation
Step 1: Resistance of wire: R ∝ (1)/(r²)
Step 2: Doubling radius makes resistance one–fourth.
Step 3: In meter bridge, balancing length is proportional to resistance: x=(x)/(4)
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