4.15 During a rotational moulding operation an aluminium mould with a uniform thickness of 3 mm is put into an oven at 300 °C. If the initial temperature of the mould is 23 °C, estimate the time taken for it to reach 250 °C. The natural convection heat transfer coefficient is 28.4 J/m²s K and the thermal diffusivity and conductivity of aluminium may be taken as 8.6 x 10-5 m²/s and 230.1 J/ms K respectively.

4.15 During a rotational moulding operation an aluminium mould with a uniform thickness of 3 mm is put into an oven at 300 °C. If the initial temperature of the mould is 23 °C, estimate the time taken for it to reach 250 °C. The natural convection heat transfer coefficient is 28.4 J/m²s K and the thermal diffusivity and conductivity of aluminium may be taken as 8.6 x 10-5 m²/s and 230.1 J/ms K respectively.

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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