solve all 4, show assumptions and comments for each. 1. A 0.75-m x 1.5-m window is constructed of 6-mm-thick glass. On a cold night, the inside andoutside surface temperatures of the glass are 16°C and -24°C, respectively.(a) What is the rate of heat loss through the glass?(b) The window is replaced by a double-paned window, in which two panes of glass areseparated by an air space. If the spacing of the panes is 13 mm and the glass surfacetemperatures in contact with the interior air space are 12°C and -18°C, what is the newrate of heat loss from the window? (Hint: since the temperatures on the inside glasssurfaces are given, you need only analyze conduction across the air gap.)2. The convection heat transfer coefficient can have a great effect on how a personexperiences temperature. Determine the convection heat flux from a person's hand in eachof the circumstances below. In each case, the person's hand can be assumed to have asurface temperature of 30°C.(a) Hand outside the window of a car moving at 20 mph in air at -15°C with a convectioncoefficient of 40 W/m²-K.(b) Hand in a slow moving stream of water at 10°C with a convection coefficient of 900W/m²-K.(c) Hand in still air in an air conditioned room at 20°C with a convection coefficient of 3W/m²-K.3. Both convection and radiation heat transfer can be important in situations where the heattransfer coefficient is relatively low. A steam pipe running through a factory is 30 m longand has a diameter of 15 cm. The steam maintains the outside surface temperature of thepipe at 165°C, and the emissivity of the pipe's surface is = 0.8. The natural convectionheat transfer coefficient is 8 W/m²-K. Determine the heat loss rate from the pipe to thesurrounding air and walls, both of which are at a temperature of 25°C.4. The air temperature in a room is maintained at 20°C year-round, but the wall temperatureis approximately 27°C in the summer and 14°C in the winter. Determine the total(convection + radiation) rates of heat transfer from a person in this room in both winter andsummer if the exposed surface area, emissivity, convection coefficient, and the averageouter surface temperature of the person are 1.8 m², 0.8, 4 W/m²-K, and 31°C, respectively. k (glass) = 1.4 W/m-K, from Table A.3k (air) = 0.0239 W/m-K, from Table A.4, property evaluated @ 270 K

“Since you have posted multiple questions with multiple sub parts, we will provide the solution only…

1. A 0.75-m x 1.5-m window is constructe outside surface temperatures of the gla (a) What is the rate of heat loss throug (b) The window is replaced by a double separated by an air space. If the spa temperatures in contact with the int rate of heat loss from the window? surfaces are given, you need only ar

1. A 0.75-m x 1.5-m window is constructe outside surface temperatures of the gla (a) What is the rate of heat loss throug (b) The window is replaced by a double separated by an air space. If the spa temperatures in contact with the int rate of heat loss from the window? surfaces are given, you need only ar

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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1) The heat flux and surface temperature of a board are related to each other with the thickness written below. What is the heat conduction coefficient of the board? Accept conditions; a) One dimensional heat transfer in x direction, b) continuous heat transfer (stady state) c) properties do not change constantly. TA T = 60 C 9:-40W/m² T=20°C +L=0.05m
2. Calculate the heat loss for the structure described below. Use the indoor design setpoint of 70°F. ● . . . ● ● Hint: Utilize the Q=U*A*(ti-to) & Q = U'*P*(ti-to). Make sure to reference the following tables and examples to help assist you solve this problem; Table 5-5a, Table 5-8, Table 5-4a, Example 5-3, Eq. 5-23, and Fig 5-8. Given: i. Location: Des Moines, IA @ 99% winter OAT ii. Walls: Table 5.7, Construction 2 iii. Floor: Concrete slab with 2-ft, R-5.4, vertical edge insulation iv. Windows: Double-Insulating Glass; 1/4-in. air space; e = 0.6 on surface 2, 3x4-ft, double hung, reinforced vinyl frame; three on each side v. vi. Roof-Ceiling: Same as Example 5.3, height of 8-ft vii. House Plan: Single story, 36-ft x 64-ft Doors: Wood, 1-3/4-in. panel doors with metal storm doors, three each, 3x6.75-ft Qwindows = Qdoors= Qwalls = Qroof/ceiling= Qfloor = QTOTAL = Btu/(hroft²0F) Btu/h Heat Loss Btu/h Heat Loss Btu/h Heat Loss Btu/h Heat Loss Btu/h Heat Loss
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Q1. Find the heat flow rate through the composite wall as shown in Fig. below. Assume one dimensional flow & the area is variable for each layer. Where: 60°C kA = 152 W/m°C, kB = 31 W/m°C, cm kC = 68 W/m°C and 7 cm D %3D B kD = 53 W/m°C. 400°C 10 cm 5 cm 8 cm
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Sipho’s mother is making a fire in the stove inside a shack using coal. A fan is used to extract the flue gasfrom the fire via a chimney made of zinc material. The wall thickness of Chimney is L=4mm and the walltemperature of the chimney on the flue gas side is T_si=60˚C. Sipho, playing outside next to the chimneyexperiences an ambient temperature of 20˚C. The surrounding temperature is T_sur=35˚C and the emissivityis ε=0.95. Assume the convection coefficient is 20W/m2K and the chimney is grey material.Under these conditions determine the outer surface (air side) temperature T_so=? of the chimney.
For the system: x:(t) f(t) M1 surface friction - f, = 6.0 Nm/s Find an equation that relates settling time of the velocity of the mass to M. b. Find an equation that relates rise time of the velocity of the mass to M.