Question

2. A 25 cm circular burner on the stove top of an electrical range can be approximated as a black body for radiation. If this burner is turned on to

reach a surface temperature of 230 °C (no pot or pan on the burner), what is the rate of heat transfer to the room with surroundings and air temperature of 24 °C: A. by radiation B. by free convection (see Chapter 9 correlations) C. if the efficiency of the burners is 85% (i.e., 15% of the electrical energy goes to something besides heat), how much electricity is required to run the burner (in Watts)? D. At what wavelength is spectral emission a maximum? (Use Wien's displacement law, equation 12.25 or 12.31depending on 6th/7th edition of the textbook) E. Is this radiation (part D) in the ultraviolet, visible or infrared region of the radiation spectrum?

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