subject
Engineering, 16.04.2020 21:57 daemonacoster

The emissivity of a surface coated with aluminum oxide can be approximated to be 0.15 for radiation at wave- lengths less than 5 mm and 0.9 for radiation at wavelengths greater than 5 mm. Determine the average emissivity of this surface at (a) 5800 K and (b) 300 K. What can you say about the absorptivity of this surface for radiation coming from sources at 5800 K and 300 K

ansver
Answers: 3

Another question on Engineering

question
Engineering, 04.07.2019 18:10
Carbon dioxide gas expands isotherm a turbine from 1 mpa, 500 k at 200 kpa. assuming the ideal gas model and neglecting the kinetic and potential energies, determine the change in entropy, heat transfer and work for each kilogram of co2.
Answers: 2
question
Engineering, 04.07.2019 18:10
Draw the engineering stress-strain curve for (a) bcc; (b) fcc metals and mark important points.
Answers: 1
question
Engineering, 04.07.2019 18:20
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
question
Engineering, 04.07.2019 18:20
Acertain flow of air (at stp) has a velocity distribution given by v i (in ft/s). if this flow is going through a 4 ft square area in the yz-plane (centered at the origin), what is the mass flow rate (in lbm/s)?
Answers: 2
You know the right answer?
The emissivity of a surface coated with aluminum oxide can be approximated to be 0.15 for radiation...
Questions
question
World Languages, 02.11.2020 22:40
question
Mathematics, 02.11.2020 22:40
question
History, 02.11.2020 22:40
question
Mathematics, 02.11.2020 22:40
Questions on the website: 13722367