A galvanometer having coil resistance 10 shows a full scale deflection for a current of 3 mA. For it to measure a current of 8 A, the value of the shunt should be:
(1) 3.75 10-3
[figure]
S= IgGI-Ig
G and S are in parallel: IgG=(I-Ig)S
S= 3 10-3 108-0.003
= 0.037.997 3.75 10-3
Answer: (1)
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