Question

When a galvanometer is shunted by resistance S, its current capacity increases n times. If the same galvanometer is shunted by another resistance S', its current capacity will increase by n' is given by

• A. $ \frac{(n+1)S}{S'} $
• B. $ \frac{S(n-1)+S'}{S'} $
• C. $ \frac{n+S}{S'} $
• D. $ \frac{S(n-1)-S'}{S'} $

Answer 1

The Correct Option is B

Using the relation $ S=\frac{G}{(n-1)} $ $ \Rightarrow $ $ G=S(n-1) $ and $ S'\frac{G}{(n'-1)} $ $ \Rightarrow $ $ n'=\frac{G+S'}{S'} $ $ \therefore $ $ n'=\frac{S(n-1)+S'}{S'} $