A thin board of 0.5 cm thickness is exposed to a fluidof T, = 22°C and h = 30 W/m².K from one side withan emissivity of 0.7 where it faces a surroundingwhose temperature is Tsur = 30°C. A heat flux of q" =3500 W/m? is applied to the other side. Each side hasan area of 12cm×12cm.Tsur(a) If the board has the following properties: k = 15.1W/m.K, c, = 480 J/kg.K and p = 8055 kg/m²,express an equation for the variation oftemperature with respect to time.(b) Find the initial time rate of change of the boardtemperature if the initial board temperature isq"h50°C.

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A thin board of 0.5 cm thickness is exposed to a fluid of T, = 22°C and h = 30 W/m².K from one side with an emissivity of 0.7 where it faces a surrounding whose temperature is Tsur = 30°C. A heat flux of q" = 3500 W/m² is applied to the other side. Each side has an area of 12cm× 12cm. (a) If the board has the following properties: k = 15.1 W/m.K, c, = 480 J/kg.K and p = 8055 kg/m³, express an equation for the variation of temperature with respect to time. (b) Find the initial time rate of change of the board temperature if the initial board temperature is 50°C.

A thin board of 0.5 cm thickness is exposed to a fluid of T, = 22°C and h = 30 W/m².K from one side with an emissivity of 0.7 where it faces a surrounding whose temperature is Tsur = 30°C. A heat flux of q" = 3500 W/m² is applied to the other side. Each side has an area of 12cm× 12cm. (a) If the board has the following properties: k = 15.1 W/m.K, c, = 480 J/kg.K and p = 8055 kg/m³, express an equation for the variation of temperature with respect to time. (b) Find the initial time rate of change of the board temperature if the initial board temperature is 50°C.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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