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The resistance of moving coil galvanomet...

The resistance of moving coil galvanometer is made twice its original value in order to increase current sensitivity by 50% Will the voltage sensitivity change ? If so, by how much?

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Yes voltage sensitvity will change .
Voltage sensitivity is `V_(s) = (I_(s))/(R)`
When the resistance is doubled, then new resistance is `R = 2R`
Increase in current sensitivity is `V_(S) = ((3)/(2) I_(s))/(2R) = (3)/(4)V_(s)` .
Hence , the voltage sensitivity decreases . The percentage decrease in voltage sensitivity is `(V_(s) - V_(s))/(V) xx 100% = 25%` .
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