JEE PHYSICS MCQ: CURRENT ELECTRICITY

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Application +4 | -1

The thermo emf of copper-constantan couple is

40\,\mu V

per degree. The smallest temperature difference that can be detected with this couple and a galvanometer of 100Ω resistance capable of measuring the maximum current of

1\,\,\mu A

View answer and explanation

Correct option: D

2.5\,{\,^0}\mathrm{C}

Option D (

2.5\,{\,^0}\mathrm{C}

) is correct because it is the smallest temperature difference that produces a measurable current in the galvanometer.

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