Thermal Storage Solar heating of a house is much more efficient if there is a way to store the thermal energy collected during the day to warm the house at night. Suppose one solar-heated home utilizes a concrete slab of area 12 m2 and 25 cm thick. (a) If the density of concrete is 2400kg/m3, what is the mass of the slab? (b) The slab is exposed to sunlight and absorbs energy at a rate of 1.4 × 107 J/h for 10 h. If it begins the day at 22 °C and has a specific heat of 750J/(kg.K), what is its temperature at sunset? (c) Model the concrete slab as being surrounded on both sides (contact area 24 m2) with a 2.0-m-thick layer of air in contact with a surface that is 5.0 °C cooler than the concrete. At sunset, what is the rate at which the concrete loses thermal energy by
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