Q1. A 1200-Wiron is left on the ironing board with its base exposed to the air (Figure 1). About 90 percent of the heat generated in the iron is dissipated through its base whose surface area is 150 cm?, and the remaining 10 percent through other surfaces. Assuming the heat transfer from the surface to be uniform determine (a) the amount of heat the iron dissipates during a 1- hour period, in kWh and (b) the total cost of the electrical energy consumed during this 1-hour period. Take the unit cost of electricity to be $0.07/kWh. Iron 1200 W

Q1. A 1200-Wiron is left on the ironing board with its base exposed to the air (Figure 1). About 90 percent of the heat generated in the iron is dissipated through its base whose surface area is 150 cm?, and the remaining 10 percent through other surfaces. Assuming the heat transfer from the surface to be uniform determine (a) the amount of heat the iron dissipates during a 1- hour period, in kWh and (b) the total cost of the electrical energy consumed during this 1-hour period. Take the unit cost of electricity to be $0.07/kWh. Iron 1200 W

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.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.56P

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