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Question
If the current is doubled, the deflection is also doubled in
Options
a tangent galvanometer
a moving-coil galvanometer
both
none
Solution
a moving coil galvanometer
The current and deflection dependence of a moving coil galvanometer is given by `i = k/(nAB)θ ⇒ i ∝ θ`
Therefore, if we double the current, the deflection also gets doubled.
However, in a tangent galvanometer, i ∝ tan θ; that is, there is no direct relation between θ and current.
Hence, the correct option is (b).
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