Current Electricity and Electrical InstrumentHard
Question
The resistance of the rheostat shown in figure is 30 Ω. Neglecting the ammeter resistance, the ratio of minimum and maximum currents through the ammeter, as the rheostat is varied, will be :
Options
A.
B.
C.
D.
Solution
For Imax , Rh is minimum which is zero .
Imax =
Amp.
for Imin , Rh is maximum which is 30Ω.
Imin =
Amp.
= 
Amp. Ans.
Imax =
Amp.for Imin , Rh is maximum which is 30Ω.
Imin =
Amp. = Amp. Ans. Create a free account to view solution
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