An electric device made of copper stands on an insulating carpet in a breezy room at 20°C. A fan is set in the room to ensure a continuous air circulation. Determine the total rate of heat transfer from the device if the average values of its exposed surface area and outer surface temperature are 2.5 m² and 30°C, respectively.

An electric device made of copper stands on an insulating carpet in a breezy room at 20°C. A fan is set in the room to ensure a continuous air circulation. Determine the total rate of heat transfer from the device if the average values of its exposed surface area and outer surface temperature are 2.5 m² and 30°C, respectively.

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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1.60 Two electric resistance heaters with a 20 cm length and a 2 cm diameter are inserted into a well-insulated 40-L tank of water that is initially at 300 K. If each heater dissipates 500 W, what is the time required for bringing the water temperature in the tank to 340 K? State your assumption for your analysis.
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