Two parallel discs of 1m diameter are situated 2m apart in surroundings at a temperature of 20 oC. The inner side of one disc has an emissivity of 0.5 and is maintained at 500 oC by electric resistance heating and the outer side of the disc is well insulated. The other disc is open to radiation on both sides and reaches an equilibrium temperature. Calculate this equilibrium temperature and the heat flow rate from the first disc, assuming heat transfer is entirely by radiation.

Q: Consider a person whose exposed surface area is 1.7 m², emissivity is 0.7, and surface temperature…

A: (a) Write the given data. A=1.7 m2ε=0.7Ts=32 °C=305 KTw=300 K

Q: A solid sphere of radius R = 8.0 cm uniformly generates 5 × 10° W/m³ of heat within it. Surrounding…

A:

Q: Consider a large plane wall of thickness L = 0.8 ft and thermal conductivity K=1.2 Btu/h-ft-*F. The…

A: GivenL=0.8 ftk=1.2 Btu/h ftoFε=0.80α=0.60T1=524 Rq˙solar=300 Btu/h ft2Tsurr=0Kσ=0.1714×10-8 Btu/h…

Q: Estimatethe heat transfer from a 240 C sphere which has an emissivity of 0.90 if it suspended in a…

A: Given data,  T= 240°C = 513 K  t= -10°C = 263 K  e= 0.9  d= 40 cm = 0.4 m

Q: The furnace wall shown in the figure is made of a material with a thermal conductivity of 5 W / m °…

A: Given data: Thermal conductivity of wall = 5 W/m °C                     Emissivity = 0.95…

Q: The door of an oven in the kitchen of a house is 0.5 m high and 0.7 m wide. When the oven is…

A: Given, Outside temperature of the door, To=32°C=32+273 K=305 K   Temperature of the room,…

Q: A person stands in front of a fire at 650°C in a room where air is at 5°C. Assuming the body…

A: Answer: The net heat flow from the body is 291.1 W.

Q: The door of an oven in the kitchen of a house is 0.5 m high and 0.7 m wide. When the oven is…

A: Data given-. σ = 5.67 x 10-8 W / m^2K^4  g = 9.81 m / s2  Tsurface = 32° C = 305 K  Toutside = 22° C…

Q: The roof of an automobile can be thought of as a flat plate with insulated bottom surface. Solar…

A:

Q: A man is working in a chamber enclosed with black walls. If the air around the worker is at 20oC,…

A: Given data: Tw=100°C=373 KTair=20°Ch=15 W/m2°Cε=0.8 Need to determine the temperature will the…

Q: Calculate the heat transfer between two (50*40 cm) parallel plates at constant temperatures of 71 =…

A:

Q: Ex2. Two large parallel plates are exchanging radiation. One plate has a temperature of 1000 K and…

A:

Q: Q3: Consider a (15cm x 20cm) printed circuit board (PCB) that has electronic components on one side…

A: Given data: Calculate the average temperature of the surrounding.

Q: A radiant heating lamp has a surface temperature of 800 K with ε = 0.6 How large a surface area is…

A: Data given-  T = 800 K  ε = 0.6  Q = 350 W

Q: 1- what is the difference between the steady heat transfer and transient heat transfer? 2-Why is the…

A: 1) steady state heat transfer means the temperature does not vary with respect to time and the…

Q: Discuss the heat transfer mechanisms associated with the cooking of a kitchen in microwave and…

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Q: 7.5 m 7.5 m 7.5 m Which of the two configurations above should a company use if it plans on using a…

A: In this problem, we have to calculate the heat transfer through the wall of the both the…

Q: Consider a person whose exposed surface area is 1.5 m2, emissivity is 0.5, and surface temperature…

A:

Q: A 50-cm x 50-cm circuit board that contains 121 square chips on one side is to be cooled by combined…

A:

Q: A double-glazed window assembly consists of two glasses, each 6 mm thick, and an air gap of 6 mm…

A:

Q: Find heat transfer between the plates in kW/m2

A: Given data; Two large parralel plates having a gap=10 mm  T1=1000K   T2=400K   ε1=0.5    ε2=0.25…

Q: Find the percentage of reduction in heat transfer if the heater is completely covered by radiation…

A:

Q: The Stefan-Boltzmann equation of thermal radiation applicable for the black body is given by which…

A: Stefan Boltzmann law states that for an ideal hot object radiator, the energy emitted is directly…

Q: A 50 cm x 50 cm square circuit board with chips on one side at 25 °C by vertical convection and…

A: Note: Given value of power emitted by one chip is larger than the total heat loss from the circuit…

Q: A certain 1m body at 20 C is display on a top of a building during the night. the body sees nothing…

A: Given data , e= 0.9  Temperature to be maintained is  T= 23°C= 296 K  T1=110 K  t= 20°C

Q: radiation equilibrium temperature of the plate

A: Given data; Flat plate made of cast iron is exposed to a solar flux=600 W/m2Ambient temp.=250CCast…

Q: The horizontal roof of a building has an emittance of 0.9. Air temperature is 1oC on a clear night.…

A: Conduction and convection heat transfer needed the use of a material medium to transfer heat from…

Q: A 2-m-diameter thin-walled stainless steel spherical tank is filled with chemicals undergoing a…

A: Given data as per question Diameter =2 m Surface temperature = 500 c Air temperature  = 200 c…

Q: 2. Consider steady heat transfer between two large parallel plates at constant temperatures of T1 =…

A: Given data: T1=295 KT2=155 KL=2 cm Need to determine the rate of heat transfer.

Q: The glass surfaces are polished, having an emissivity of 0.095. The diameters of the inner and outer…

A: The heat transfer coefficient due to radiation through the cylindrical surface from the inner to the…

Q: 2 inch OD during a visit to a plastic sheet factory 60 m long section of a horizontal steam pipe…

A:

Q: E : Consider a large plan wall of thickness L=0.06 m and thermal conductivity k-1.2 W/m °C in space.…

A: Given that ε=0.85 , solar absorptivity(α)=0.26 T1=300K  ,  L=0.06m  ,  k=1.2  , qsolar=800W/m2 outer…

Q: Consider a silicon wafer positioned in a furnace that is zone-heated on the top section and cooled…

A:

Q: You are designing a chamber to contain the radiation emitted by nuclear decay during a fusion…

A: Determine the expression for the temperature distribution in the wall, T(x) based on the given…

Q: A flat-plate collector with one glass cover is placed in horizontal. The absorber plate temperature…

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Q: thermocouple shielded by a layer of aluminum foil and copper with an emissivity of 0.05 and 0.02 is…

A: Given: A thermocouple shielded by a layer of aluminum foil and copper with an emissivity of 0.05 and…

Q: 2. (a) Consider a 25-cm-diameter spherical ball at 700 K suspended in air and assume the…

A: Note - As per our guidelines we are supposed to answeronly one question. Kindly repost other…

Q: a certain body at 20 C is display on a top of a building during the night. the body sees nothing but…

A: Given data,  T1= 20°C = 293K  T=23°C = 296 K  To=110 K  ε= 0.92  Let the Stefan Boltzmann constant…

Q: 2. A 2-meter section of a 2-cm diameter metal pipe passes through an enclosed furnace. The…

A:

Q: A 1-m diameter spherical solid receives heat from a source at 160°C by radiation and transfers heat…

A: Given: Diameter of the solid sphere is 1 m. Source temperature is 160°C. Surrounding temperature is…

Q: Consider a 0.6-m × 0.6-m thin square plate in a room at 30°C. Both sides of the plate are maintained…

A: Given: The average film temperature. The properties of air at 60°C.

Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.