NEET Exam Model Paper 10

The potential difference across ammeter and shunt is the same
Let ia is the current. Flowing through ammeter and i the total current. So, a current i−ia will flow through shunt resistancePotential difference across ammeter and shame resistance is the same
That ia×R=(i−ia)×S
r S=

iaR

i−ia

..........(i)
Given ia=100A,i=750A,R=13Ω
Hence, S=

100×13

750−100

=2Ω