Engineering, 02.10.2019 05:20, cocacola8268
One homeowner uses electricity to heat a home (with 100% efficiency) at an annual cost of $2600. a second homeowner uses a heat pump with a coefficient of performance of 7 to heat an identical home. what is the second homeowner's annual heating cost?
Answers: 1
Engineering, 04.07.2019 18:20, safiyabrowne7594
Ahe-xe mixture containing a 0.75 mole fraction of helium is used for cooling electronics in an avionics application. at a temperature of 300 k and atmospheric pressure, calculate the mass fraction of helium and the mass density, molar concentration and molecular weight of the mixture. if the cooling capacity is 10 l, what is the mass of the coolant?
Answers: 3
Engineering, 04.07.2019 19:20, anggar20
Air enters a horizontal, constant-diameter heating duct operating at steady state at 290 k, 1 bar, with a volumetric flow rate of 0.25 m°/s, and exits at 325 k, 0.95 bar. the flow area is 0.04 m2. assuming the ideal gas model with k = 1.4 for the air, determine (a) the velocity at the inlet and exit, each in m/s, and (c) the rate of heat transfer, in kw flow rate, in kg/s, (b) the mass kg 0.3
Answers: 2
Engineering, 06.07.2019 04:10, trist22
An inventor claims to have developed a reversed heat engine (ie. a heat pump) which is able to deliver 10 kj heat into the room at 20°c from outside ambient temperature of -10°c by consuming only 2 kj electricity in winter. this claim is a)-impossible b)-possible only if the heat pump is ideal c)-practically possible d)-unable to be assessed as it depends on the working fluid used in the heat pump.
Answers: 2
One homeowner uses electricity to heat a home (with 100% efficiency) at an annual cost of $2600. a s...
Mathematics, 07.03.2020 02:38