A galvanometer has a coil of resistance 
and gives full scale deflection for 30 mA current. If it is to work as a voltmeter of 30 V, the resistance required to be added is
A
B
C
D
Text Solution
Verified by ExpertsThe correct answer is:
B
Let, R x resistance be connected in series to convert galvanometer to voltmeter.
According to the question, 
(Current corresponding to full scale deflection)
Now, we can write, 
(i)
Given, 
From Eq. (i), we get
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