Physics-
General
Easy
Question
Consider two different ammeters in which the deflections of the needle are proportional to current. The first ammeter is connected to a resistor of resistance 
and the second to a resistor of unknown resistance 
. At first the ammeters are connected in series between points A and B [as shown in fig. a)]. In this case the readings of the ammeters are 
and 
Then the ammeters are connected parallel between A and B as shown in fig.(B) and indicated 
and 
Determine the unknown resistance of the second resistor.
The correct answer is:
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