Current Electricity and Electrical InstrumentHard
Question
A micro-ammeter has a resistance of 100 Ω and full scale range of 50 mA. It can be used as a voltmeter and an ammeter of a higher range provided a resistance is added to it. Pick the correct range and resistance combination (s) :
Options
A.50 V range with 10 kΩ resistance is series
B.10 V range with 200 kΩ resistance in series
C.5 mA range with 1 Ω resistance in parallel
D.10 mA range with 1Ω resistance in parallel
Solution
for 50 V, RV = 
= 1000KΩ in series
for 10V, RV =
= 200 KΩ in series
for 5 mA, Rs =
in parallel
for 10 mA, Rs =
= 
Ω in parallel
= 1000KΩ in series for 10V, RV =
= 200 KΩ in seriesfor 5 mA, Rs =
in parallel for 10 mA, Rs =
= Ω in parallelCreate a free account to view solution
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