Home
Answered Questions
Physics
A: Determine The Effective R-value For A 7.7 Ft Long Section Of The Wall With The Cross-section Sho

A: Determine the effective R-value for a 7.7 ft long section of
the wall with the cross-section shown above.
(ft^{2}-hr-°F/BTU)

Hint #1: | The heat has two options through which to travel: 1 and 3, or 2 and 3. |

Hint #2: | Find R_{eff} for 1 and 3 in series, and then 2 and 3 in
series, then combine those two values as a parallel system. |

Hint #3: | The area for the R calculation is the length times the height |

B: Determine the magnitude of the rate of heat flow through a
7.7 ft long section of the wall with the cross-section shown
above.

(include units with answer)

X1 = 0.6 ft X3 = 0.2 ft H1 = 5.5 ft H2 = 6.5 ft L = 7.7 ft K1 = 0.15 BTU/(hr-ft-°F) K2 = 1.06 BTU/(hr-ft-°F) K3 = 0.03 BTU/(hr-ft-°F) T1 = 22 °F T3 = 69 °F A wall is made of three different materials as shown. EXAMPLE ES IMAGES DISCUSS UNITS STATS HELP PREFERENCES Description Answer Chk History y_ 20 pts. 100% Determine the effective R-value for a 7.7 ft long section of wall with the cross section shown above. (fta-hr- °F/BTU) # tries: 0 Show Details 2% try penalty Hints: 3,2 Determine the magnitude of the rate of heat flow through a 7.7 ft long section of wall with the cross section shown above. (include units with answer) 20 pts. 100% # tries: 0 Show Details Format Check 2% try penalty Hints: 0,0