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Question
A tangent galvanometer is connected directly to an ideal battery. If the number of turns in the coil is doubled the deflection will
Options
increase
decrease
remain unchanged
either increase or decrease
Solution
remain unchanged
For a tangent galvanometer, deflection is given by
`θ = tan^-1(i/k)`
Here, k is the constant called reduction factor.
From the above formula, we can say that deflection is independent of the number of turns.
Hence, on doubling the number of turns, deflection remains the same.
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