The galvanometer circuit includes a thermocouple consisting of copper and constantan wires 1 m long and 0.2 mm in diameter. The sensitivity of the galvanometer is 10-6 A per scale division; its internal resistance is 50 ohms. By how many divisions will the galvanometer needle deviate if the thermocouple junction is overheated by 50° C relative to the ambient temperature? E.d. With. thermocouples 40 µV/deg, resistivity of constantan 0.50·10-4 ohm·cm and copper 0.17·10-5 ohm·cm.

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