Which principle relates temperature differences to emf generated in a single homogeneous wire?
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Answer: B. Thomson effect
Explanation
The Thomson effect describes the electromotive force generated in a single homogeneous wire subjected to a temperature gradient. Passing electrical current through a single conductor experiencing temperature differences causes heat absorption or generation. This thermodynamic phenomenon distinguishes itself from multi-metal junction effects by occurring entirely within one continuous wire. Thermoelectric effects govern how temperature gradients and electrical potentials interact within metallic conductor materials. William Thomson discovered that heat is absorbed or evolved when current flows along a thermally graded conductor. Homogeneous wires possess uniform chemical composition and physical structure throughout their entire continuous length.
Precise thermodynamic modeling of thermoelectric generators requires accounting for Thomson heat contributions along legs. Understanding single-wire thermal EMF generation helps engineers minimize parasitic voltage errors in thermocouple circuits. Advanced temperature sensor research utilizes thermoelectric principles to improve energy conversion efficiencies. Peltier effect describes heat absorption or generation occurring at junctions of two dissimilar metals when current passes. Seebeck effect involves electromotive force generation across two dissimilar metal junctions maintained at different temperatures. Selecting none of these is incorrect because the Thomson effect correctly answers the single homogeneous wire phenomenon.
- Subject
- Engineering
- Category
- Chemical Engineering
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- —
- Difficulty
- medium
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