moving-coil instrument has a resistance of 5 Ω between terminals and full scale deflection is obtained with a current of 15 mA. This instrument is to be used with a manganin shunt to measure 100 A at full scale. Calculate the error caused by a 10°C rise in temperature: (a) When the internal resistance of 5 Ω is due to copper only. (b) When a 40Ω manganin swamping resistance is used in series with a copper coil of 1Ω resistance. The resistance temperature co-efficients of copper and manganin are 0.4%/°C and 0.015%/°C rise respectively.