A 4.5 cm diameter frozen beef meatball is being defrosted in the refrigerator at 5 °C. The meatball is initially at -20 °C and has a density of 1080 kg/m³, a specific heat capacity of 3.1 kJ/(kg. K) and a thermal conductivity of 0.56 W/(m. K). The convective heat transfer coefficient from the refrigerator air to the meatball is 60 W/(m². K). Calculate the Biot number for heat transfer to the meatball: Estimate the mass of the meatball: kg Hence, estimate the time it would take for the centre of the meatball to reach -5 °C: hours After this time, what would the temperature halfway between the centre and the surface of the meatball be? °C

A 4.5 cm diameter frozen beef meatball is being defrosted in the refrigerator at 5 °C. The meatball is initially at -20 °C and has a density of 1080 kg/m³, a specific heat capacity of 3.1 kJ/(kg. K) and a thermal conductivity of 0.56 W/(m. K). The convective heat transfer coefficient from the refrigerator air to the meatball is 60 W/(m². K). Calculate the Biot number for heat transfer to the meatball: Estimate the mass of the meatball: kg Hence, estimate the time it would take for the centre of the meatball to reach -5 °C: hours After this time, what would the temperature halfway between the centre and the surface of the meatball be? °C

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter21: Heat And The First Law Of Thermodynamics

Section: Chapter Questions

Problem 31PQ: Consider the latent heat of fusion and the latent heat of vaporization for H2O, 3.33 105 J/kg and...

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