In an ammeter 0.2% of main current passes through the galvanometer. If resistance of galvanometer is G, the resistance of ammeter will be [AIPMT 2014]
A) \[\frac{1}{499}G\]
B) \[\frac{499}{500}G\]
C) \[\frac{1}{500}G\]
D) \[\frac{500}{499}G\]
Correct Answer:
A
Solution :
For ammeter \[0.0002l\times G=0.998l\times {{r}_{g}}\] \[{{r}_{g}}=\frac{0.002}{0.998}G\] Þ \[{{r}_{g}}=0.002004G=\frac{1}{499}\times G\] Resistance of ammeter is approximately equal to resistance of shunts.