The current sensitivity is given as
Si=CNBA.
The voltage sensitivity is
Sv=(CRNAB), where R is the galvanometer resistance.
Since the resistance is constant,
ΔSi=(ΔSv)
Hence, the percentage change in voltage sensitivity is,
(ΔSv)=+25.
JEE Main 2023 — Physics Electromagnetism
The current sensitivity of moving coil galvanometer is increased by 25. This increase is achieved only changing in the number of turns of coils and area of cross section of the wire while keeping the resistance of galvanometer coil constant. The percentage change in the voltage sensitivity will be:
Held on 11 Apr 2023 · Verified 6 Jul 2026.
+25
−50
−25
Zero
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