-
A thermocouple of negligible resistance produces an e.m.f. of 40 µV/°C in the linear range of temperature. A galvanometer of resistance 10 ohm whose sensitivity is 1µA/div, is employed with the termocouple. The smallest value of temperature difference that can be detected by the system will be
-
- 0.5°C
- 1°C
- 0.1°C
- 0.25°C
Correct Option: D
1 division = 1µA
Current for 1°C = 40μV/10 = 4μA
1μA =1/4 °C = 0.25°C.
