The thermal contact resistance at the interface of two 1-cm thick copper plates is measured to be 0.000056 m2K/W. Determine the thickness of the copper plate whose thermal resistance is equal to the thermal resistance of the interfacial contact between the two plates.

It needs 46,992 m thick

Explanation:

Copper is a metal so it has a high thermal conductivity

             σ = 380 W / m K

The resistance of thermal contact between the two plates is

             ρ = 0.000056 m² K / W

How conductivity and resistance are inverse

             σ_plate = 1 /ρ  

             σ_plate = 1 / 0.000056

             σ_plate = 17857.14 W / K m²

Let's look for the relationship between the two magnitudes

            σ-Plate / σ_cupper = 17857.14 / 380

            σ_plate / σ_cupper = 46,992 m

It needs 46,992 m thick

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