Physics, 26.11.2019 03:31, estrella7777

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 14 m2 and 21 cm thick.
a. if the density of concrete is 2400 kg/m3, what is the mass of the slab?7100kg
b. the slab is exposed to sunlight and absorbs energy at a rate of 1.9 ×107j/h for 10 h. if it begins the day at 25 ∘c and has a specific heat of 750 j/(kg⋅k), what is its temperature at sunset?
c. model the concrete slab as being surrounded on both sides (contact area 28 m2) with a 1.7-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 conduction through the air layer?
d. model the concrete slab as having a surface area of 24 m2 and surrounded by an environment 5.0 ∘c cooler than the concrete. if its emissivity is 0.92, what is the rate at which the concrete loses thermal energy by radiation at sunset?
i need b, c, and d! show all work.

Answers: 1

Show answers

Other questions on the subject: Physics

Physics, 21.06.2019 20:20, pamelperezz26

Ateam of astronauts is on a mission to land on and explore a large asteroid. in addition to collecting samples and performing experiments, one of their tasks is to demonstrate the concept of the escape speed by throwing rocks straight up at various initial speeds. with what minimum initial speed vesc will the rocks need to be thrown in order for them never to "fall" back to the asteroid? assume that the asteroid is approximately spherical, with an average density p 3.84 x108 g/m3 and volume v 2.17 x 1012 m3 recall that the universal gravitational constant is g 6.67 x 10-11 n m2/kg2

Answers: 2

continue

Physics, 22.06.2019 02:10, lunnar2003

How many hydrogen (h) atoms are in one molecule of sulfuric acid, h2so4? (1 points) 1 2 4 7

Answers: 3

continue

Physics, 22.06.2019 05:00, shimmerandshine1

At time t=0, a particle is located at the point (3,6,9). it travels in a straight line to the point (5,2,7), has speed 8 at (3,6,9) and constant acceleration 2i−4j−2k. find an equation for the position vector of the particle.

Answers: 2

continue

Physics, 22.06.2019 06:20, lolweapon

Atwo-stage air compressor operates at steady state, compression 10m^3/min of air from 100 kpa and 300k to 1200 kpa. an intercooler between the two stages cools the air to 300k at a constant pressure of 350 kpa. the compression processes are isentropic. a) calculate the power required to run the compressor, in kw b) compare the result to the power required for isentropic compression from the same inlet state to the same final pressure.

Answers: 1

continue

Do you know the correct answer?

Solar heating of a house is much more efficient if there is a way to store the thermal energy collec...