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A thermocouple of negligible resistance ...

A thermocouple of negligible resistance produces an emf fo `40 mu V//^(@)C` in the linear range of temperature. A galvanometer of resistance `10 Omega` whose sensitivity is `1 mu A//div` is employed with the thermocouple. The smallest value of temperature difference that can be detected by the system will

A

`0.25^(@)C`

B

`0.5^(@)C`

C

`1^(@)C`

D

`0.1^(@)C`

Text Solution

Verified by Experts

Given: `(DeltaV)/(Deltatheta)=(muV)/(.^(@)C)` and `DeltaV=DeltaIR=10muV//"div"`
`rArr(Deltatheta)_("min")=(10)/(40).^(@)C=0.25^(@)C`
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