An average person generates heat at a rate of 240 Btu/h while resting in a room at 70°F. Assuming onequarter of this heat is lost from the head and taking the emissivity of the skin to be 0.9, determine the average surface temperature of the head when it is not covered. The head can be approximated as a 12-in-diameter sphere, and the interior surfaces of the room can be assumed to be at the room temperature.

Q: Consider steady heat transfer between two large parallel plates at constant temperature…

A: As per the guidelines we will answer the first three subparts for you. for the rest of the subparts…

Q: A 1000-W iron is left on the iron board with its base exposed to the air at 20°C. The convection…

A: Given, Q˙in = 1000 WT∞ = 20 °C = 293 Kh = 35 W/m2 °Cε = 0.6A = 0.02 m2

Q: During a visit to a plastic sheeting plant, it was observed that a 60-m-long section of a 2-in…

A: Write the given information. Write the expression of the film temperature. Write the properties of…

Q: During a picnic on a hot summer day, the only available drinks were those at the ambient temperature…

A: Given data: Diameter of the can, d =2.5 in. Density of water at room temperature, ρ = 62.22 lbm/ft3…

Q: Question # 2: A10-m-long section of a 6-cm-diameter horizontal hot water pipe passes through a large…

A: Given data as per the question Length of section =10 m diameter =6 cm Tmean=65+222=43.50cconsidering…

Q: Consider two identical rooms,one with a refrigerator in it and the other without one .if all the…

A:

Q: Show that the volume expansion coefficient of an ideal gas is B=1/T, where T is the absolute…

A: Assumption Pressure is constant ( P = C )   We know that change in volume due to thermal expansion…

Q: 1. A 1000-W iron is left on the iron board with its base exposed to the air at 20°C. The convection…

A: Heat Transfer

Q: A 40-cm-long, 0.6-cm-diameter electric resistance wire is used to determine the convection heat…

A: Giiven A 40-cm-long, 0.6-cm-diameter the convection heat transfer coefficient = 254 surface…

Q: What are the best possible solutions to increase the heat transfer rate of a body?

A: There are three modes of heat transfer; Conduction, convection and radiation. For these all modes we…

Q: What are the mechanisms of heat transfer? How are they distinguished from each other?

A: There are three mechanisms of heat transfer. These are given as under, (1) Conduction (2) Convection…

Q: The net radiant-heat exchange between a 20-by-20 ft rough plaster panel-heated ceiling and a…

A:

Q: Does any of the energy of the sun reach the earth by conduction or convection?

A: Since there is no atmosphere in space between the Sun and the earth, the significant portion of the…

Q: Consider a person standing in a room maintained at20°C at all times. The inner surfaces of the…

A:

Q: 02. An electronic box that consumes 180 W of power is cooled by a fan blowing air into the box…

A: We are supposed to answer only 3 parts, please post remaining parts as a separate question.

Q: A 18-m-long section of a 14-cm-diameter horizontal hot water pipe passes through a large room whose…

A:

Q: = Consider a person standing in a room at 23°C. Determine the total rate of heat transfer from this…

A:

Q: The chilling room of a meat plant is 15 m × 18 m × 5.5 m in size and has a capacity of 350 beef…

A: Given, Dimension of the plant ,V=15m×18m×5.5mNumber of beefcases, n=350Power consumed by fan,…

Q: Consider a room whose door and windows are tightly closed, and whose walls are well-insulated so…

A: The only energy interaction involved here in this question seems to be the electrical energy…

Q: 19. The inner and outer glasses of a 2-m x 2-m double pane window are at 18°C and 6°C, respectively.…

A: Given data , Area A= 2*2= 4 m2  T1= 18 °C  T2=6°C  T1-T2= 12°C L= 1 cm = 0.01 m  Space is fill with…

Q: Consider a person standing in a room at 25°C. Determine the total rate of heat transfer and the heat…

A:

Q: On a hot summer day, a workshop employee turns his fan on when he leaves the room in the morning.…

A: Given data Discuss the following scenarios related to the first law of thermodynamics.

Q: Iron with a power rating of 1200 watts is left on the ironing board. The convective heat transfer…

A:

Q: Determine the steady rate of heat transfer

A:

Q: Consider a person standing in a room maintained at 20°C at all times. The inner surfaces of the…

A:

Q: Consider a 1.2-m-high and 2-m-wide double-pane window consisting of two 0.023-mm-thick layers of…

A:

Q: Portable electric heaters are commonly used to heat small rooms. Explain the energy transformation…

A: Given:1st Law of thermodynamics: According to this law, total energy of the system is conserved,It…

Q: (a) A small body with temperature T and emissivity e is placed in a large evacuated cavity with…

A:

Q: Consider a person standing in a room at 23°C. Determine the total rate of heat transfer from this…

A:

Q: Consider a sealed 20-cm-high electronic box whose base dimensions are 40 cm x 40 cm placed in a…

A: Heat transfer through radiation is equal to the power generated. The exposed area could be…

Q: 1.) Consider a sealed 20-cm-high electronic box whose base dimensions are 40 cm x40 cm placed in a…

A:

Q: An average person body surface is approximately 2.0 m². Its skin temperature is 33°C. The convection…

A: Find convective heat transfer .

Q: Consider a sealed 20-cm-high electronic box whose base dimensions are 50 cm x 50 cm placed in a…

A: Data given-   Ts = 55+273 = 328 K  Heat is mainly transferred by radiation only .

Q: A Gasoline engine operating on an air standard condition has a clearance volume of 15cm^3 and a…

A: Given data Clearance volume = 15 cm³ Displacement volume = 100 cm³

Q: How does a fin enhance heat transfer at a surface?

A: Fins are the projections or extended surfaces protruding from hot surface into ambient fluid and…

Q: Consider a person standing in a room at 18°C. Determine the total rate of heat transfer from this…

A:

Q: An aluminum pan whose thermal conductivity is 237 W/m*^ C has a flat bottom whose diameter is 20 cm…

A: Given-Data:- Thermal Conductivity=237Wm°CThickness of aluminium pan(L)=0.6cmDiameter of Aluminium…

Q: Please check attach file

A: Given data: h = 12 m b = 2 m t = 0.023 mm k = 0.78 W/m k Separated by the vacuum = 12 mm wide h1 =…

Q: Consider a person standing in a breezy room at 20°C. Determine the total rate of heat transfer from…

A: Given: Room temperature is 20°C. Exposed area of the person is 1.6 m2. Surface temperature of the…

Q: The heat is dissipated from the plate by convection and radiation into surrounds at 20 C . Take ε…

A: Given Ta=20 0C=20+273.15 K=293.15 KTs=50 0C=50+273.15 K=323.15 K ε=0.8σ=5.67×10-8 Wm2K4h=6 W/m2K