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प्रश्न
The heat current is written as `(ΔQ)/(Δt)`. Why don't we write `(dQ)/dt?`
उत्तर
The amount of heat crossing through any cross-section of a slab in time `Δt` is called heat current.
It is written as `(ΔQ)/(Δt)` and not `(ΔQ)/(Δt)` as complete derivative . This is because the amount of heat crossing through any cross section is a function of many variables like temperature difference, area of cross-section, etc. So, we cannot write it as a complete derivative with respect to time.
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संबंधित प्रश्न
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(Wein’s constant b = 2.898 × 10-3 mK)
(A) 0.0414 × 10-6m
(B) 4.14 × 10-6m
(C) 41.4 × 10-6m
(D) 414 × 10-6m
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What is perfectly black body ? Explain Ferry’s black body.
A blackbody does not
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(c) reflect radiation
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