Thermal Storage Solar heating of a house is much more efficientif there is a way to store the thermal energy collected during theday to warm the house at night. Suppose one solar-heated homeutilizes a concrete slab of area 13 m2 and 29 cm thick.
If the density of concrete is 2400 kg/m3, what is the mass ofthe slab?
The slab is exposed to sunlight and absorbs energy at a rate of1.4 ×107J/h for 10 h. If it begins the day at 25 ∘C and has aspecific heat of 750 J/(kg⋅K), what is its temperature atsunset?
Model the concrete slab as being surrounded on both sides(contact area 26 m2) with a 1.7-m-thick layer of air in contactwith a surface that is 5.0 ∘C cooler than the concrete. At sunset,what is the rate at which the concrete loses thermal energy byconduction through the air layer?
Model the concrete slab as having a surface area of 24 m2 andsurrounded by an environment 5.0 ∘C cooler than the concrete. Ifits emissivity is 0.93, what is the rate at which the concreteloses thermal energy by radiation at sunset?
