Physics for Scientists and Engineers
6th Edition
ISBN: 9781429281843
Author: Tipler
Publisher: MAC HIGHER
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Chapter 20, Problem 50P
To determine
To Estimate: The R factor of the material.
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A glass windowpane in a home is 0.62 cm thick and has dimensions of 1.5 m × 2.2 m. On a certain day, the indoor temperature is 30°C and the outdoor temperature is 0°C.
(a) What is the rate at which energy is transferred by heat through the glass?_____W
(b) How much energy is lost through the window in one day, assuming the temperatures inside and outside remain constant?____J
Please help with the hw question?
How much fiberglass insulation (k = 0.035 W/m*K) is needed to guarantee that the outside temperature of a kitchen oven will not exceed 43 degrees Celsius? The maximum oven temperature to be maintained by the conventional type of thermostatic control is 290 degrees Celsius, the kitchen temperature may vary from 15 to 33 degrees Celsius, and the average heat transfer coefficient between the oven surface and the kitchen is 12 W/m2*K.
The north wall of an electrically heated home is 20 ft long, 10 ft high, and 1 ft thick, and is made of brick whose thermal conductivity is k = 0.42 Btu/h·ft·°F. On a certain winter night, the temperatures of the inner and the outer surfaces of the wall are measured to be at about 62°F and 25°F, respectively, for a period of 8 h. Determine (a) the rate of heat loss through the wall that night and (b) the cost of that heat loss to the home owner if the cost of electricity is $0.07/kWh.
Chapter 20 Solutions
Physics for Scientists and Engineers
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