A student staying in a room measuring 4m x 6m x 6m leaves his room on a summer morning and leaves his 150W fan on, hoping that it will be cooler when he returns in the evening. All windows and doors of his room are closed. Assuming that there is no heat transfer through the walls and windows, calculate what the room temperature will be when the student returns after 10 hours. When the student leaves the room in the morning, the room temperature is 15 ° C, the amount of air in the room is 174 kg, the specific heat value of the air is 0.718 kJ / kgoC.

A student staying in a room measuring 4m x 6m x 6m leaves his room on a summer morning and leaves his 150W fan on, hoping that it will be cooler when he returns in the evening. All windows and doors of his room are closed. Assuming that there is no heat transfer through the walls and windows, calculate what the room temperature will be when the student returns after 10 hours. When the student leaves the room in the morning, the room temperature is 15 ° C, the amount of air in the room is 174 kg, the specific heat value of the air is 0.718 kJ / kgoC.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.60P: 1.60 Two electric resistance heaters with a 20 cm length and a 2 cm diameter are inserted into a...

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