subject
Mathematics, 23.06.2019 09:00 porkhappycom

Consider a 2-m-high electric hot-water heater that has a diameter of 40 cm and maintains the hot water at 55°c. the tank is located in a small room whose average temperature is 27°c, and the heat transfer coefficients on the inner surface of the heater is 50 w/(m2 *°c), respectively. the tank is placed in another 46-cm-diameter sheet metal tank of negligible thickness, and the space between the two tanks is filled with foam insulation (k = 0.03 w/(m*°c). the heat transfer coefficient of the outer surface of the whole unit is 12 w/(m2 *°c). the thermal resistances of the water tank and the outer thin sheet metal shell are very small and can be neglected. the price of electricity if $0.08/kwh, and the home owner pays $280 a year for water heating. (a) determine the fraction of the hot-water energy cost of this household that is due to to the heat loss form the tank. hot water tank insulation kits consisting of 3-cm-thick fiberglass insulation (k = 0.035 w/m oc) large enough to wrap the entire tank are available in the market for about $30. if such an insulation is installed on this water tank by the home owner himself, how long will it take for this additional insulation to pay for itself?

ansver
Answers: 3

Another question on Mathematics

question
Mathematics, 21.06.2019 13:30
Plz me plzzzzzzz i need and plz delte this after answer
Answers: 3
question
Mathematics, 21.06.2019 19:00
Prove that quadrilateral is a rhombus.
Answers: 1
question
Mathematics, 21.06.2019 22:00
Using inductive reasoning, what is the next two numbers in this set? 1,-7,13,-19 i got the numbers 14,-26 is that right?
Answers: 2
question
Mathematics, 21.06.2019 22:30
]supplementary angles are two angles that add up to . • complementary angles are two angles that add up to degrees. • adjacent angles share a and a • congruent angles have the measure. • an triangle has one angle that is greater than 90 degrees. • a triangle with angles 45°, 45°, and 90° would be a triangle
Answers: 2
You know the right answer?
Consider a 2-m-high electric hot-water heater that has a diameter of 40 cm and maintains the hot wat...
Questions
question
History, 03.07.2019 09:00
question
Mathematics, 03.07.2019 09:00
Questions on the website: 14505247