Multiple Choice:
Username:
1. The rate of heat flow through a wall is dependent upon which of the following? a. the deltaT between inside and outside b. the R value of the wall c. the area of the wall d. all of the above
2. Which of the following strategies would reduce the heat flow through a wall the most? a. double the wall area b. double the R value c. double the deltaT d. all of the above
3. The temperature difference between inside and outside (deltaT) is partly dependent upon: a. the outside air relative humidity b. the thermostat setting c. the inside air relative humidity d. all of the above
4. The easiest way to change the deltaT is: a. change the climate b. change the thermostat setting c. change the envelope R value d. all of the above
5. Which of the following will reduce the heat flow through a building wall at noon on a hot day? a. increase wall reflectivity b. decrease wall emissivity of the exterior surface c. decrease wall reflectivity d. decrease the wall R value
6. Assuming a floor and flat roof are exposed to the same outside and inside temperatures, the rate of heat flow from outside to inside the roof is likely to be greater than in the floor because: a. The solar gain on the roof increases the effective outside temperature. b. The R values of the floor and roof are the same. c. The area of the floor and roof are the same. d. The floor and roof have different orientations with respect to the ground plane.
7. Given two walls of equal R value - one constructed of wood studs and sheathing and one constructed of masonry - which of the following is true? a. The heat from the exterior will reach the interior at about the same time for both walls. b. The heat from the exterior will reach the inside sooner through the wood wall. c. The heat from the exterior will reach the inside sooner through the masonry wall. d. There isn't enough information to answer this question.
8. Which of the following walls will absorb the most heat? a. a wall with a reflectivity of .9 b. a wall with a reflectivity of .7 c. a wall with a reflectivity of .5 d. a wall with a reflectivity of .3
9. On a clear December day at 45° North latitude, which of the following surfaces will receive the most solar radiation? a. south wall b. west wall c. east wall d. flat roof
10. On a clear June day at 45° north latitude, which of the following surfaces will receive the most solar radiation? a. south wall b. west wall c. east wall d. flat roof
11. On a clear December day at the equator, which of the following surfaces will receive the most solar radiation? a. south wall b. west wall c. east wall d. flat roof
12. In the summer at 45° north latitude, which of the following shading devices are most effective on a west elevation? a. horizontal overhang b. vertical fins perpendicular to the wall plane c. interior Venetian blinds d. exterior roll down blinds
13. Which of the following determine a building's capability to cross ventilate the heat gained in its interior? a. inlets and outlets of equal size b. unblocked air-flow paths through the building c. all windows oriented to the prevailing wind direction d. all of the above
14. In a climate with cold nights and warm sunny days, which of the following is most effective for reducing heat loss at night but allowing solar gain during the day? a. double glazing b. triple glazing c. low e glazing d. single glazing with R7 night insulation
15. Which of the following lights gives off the least heat for amount of light it generates? a. incandescent b. fluorescent c. high pressure sodium d. They all give off equal amounts of heat at the same lighting levels.
16. When an office building uses daylighting as an energy efficiency strategy, what else should be considered? a. shading b. electric lighting controls c. low contrast levels between the window wall and other surfaces d. all of the above
17. In office buildings, what often causes the daily heat gain peak? a. high outside temperature b. high internal gains c. solar gain d. all of the above
18. Which of the following is the least expensive way to decrease a house's energy use? a. specify operable windows b. specify high insulation levels c. specify thermal mass d. specify a night set back/dead band thermostat
19. A well insulated building with mass exposed on its interior and shaded south operable glazing is most well matched to which of the following climates? a. Phoenix, AZ b. Dodge City, KS c. Madison, WI d. Charleston, SC
Use this bar graph to answer questions 20 through 30. This load diagram is for a 1200 SF house located in Phoenix, AZ. The chart represents one day in March. The hours of the day are on the horizontal axis. The values on the vertical axis are Btu's. Heat gain is shown above the zero line and heat loss below the line. The building has a thermostat setting of 65 minimum (below which the furnace comes on) and 75 maximum (above which the air conditioning comes on) for all 24 hours. 20. The building would have better energy performance if which of the following were true? a. reduced heat gain b. reduced heat loss c. more efficient lights and equipment were installed d. all of the above 21. Assuming perfect mixing of heat gains and losses, in order for the building to have zero loads the: a. heat gain should equal 1/2 the heat loss b. heat gain should equal heat loss c. heat loss should equal 1/2 the heat gain d. heat loss should equal twice the heat gain 22. Which of the following causes the most heat gain in any hour? a. solar gain through windows b. walls c. roofs d. lights 23. Which of the following causes the most heat loss by conduction (primarily) in any hour? a. walls b. roofs c. floors d. windows 24. When is this building occupied ? a. from midnight to midnight (24 hours) b. from 8 am to 5 pm c. from 5 pm to 8 am d. from 9 pm to 7 am 25. What are the occupants of this building probably doing from 10:00 pm to 5:00 am? a. impossible to tell b. cooking c. sleeping d. reading 26. If this building were a very energy efficient building, any given hour's set of bars (heat gain and loss) would be: a. of equal length b. as short as possible c. both a and b d. neither a or b Use the bar graph and the following list of strategies to answer questions 27 through 30. a. shading b. cross ventilation c. stack ventilation d. light colored walls and roofs e. increased wall insulation f. decreased wall insulation g. night insulation of glazing h. increased roof insulation i. decreased roof insulation j. darker colored walls and roofs k. interior mass exposed to room air l. low e windows m. decreased infiltration n. use more efficient lights o. increase the unoccupied allowable temperature range 27. Which of the following would reduce heat gain in this building? a. a, d, f, g b. a, d, e, g c. d, h, m, n d. e, g, i, l 28. Which of the following would reduce heat loss in the building? a. b, d, e, g b. c, e, g, h c. e, m, n, o d. e, g, h, l 29. Which of the following would probably result in a loads reduction over the entire day? a. a, b, d, e b. e, g, h, k c. l, m, n, o d. all of the above 30. Which of the following could be an explanation for why the building is not cross ventilating from 11:00 am to 8:00 pm? a. The outside temperature is higher than the allowable inside temperature. b. Windows aren't oriented to the wind direction. c. There is no wind. d. all of the above
Questions 31 through 40 require the use of some bar graphs and climate data. Click here to view the graphs and climate data. The load diagram is for a 1000 SF office. The bar graphs represents four days one in March, June, September and December. The hours of the day are on the horizontal axis. The values on the vertical axis are Btu's. Heat gain is shown above the zero line and heat loss below the line. The building has a thermostat setting of 65 minimum (below which the furnace comes on) and 75 maximum (above which the air conditioning comes on) for all 24 hours. The building is occupied from 8:00 a.m. to 5:00 p.m. The lights and equipment are on during the same period. The lights are photo-controlled and will be off when there is sufficient daylight to meet the required light level.
31. Which of the following strategies would be effective during all over-heated periods (over-heated means the hours when the heat gain exceeds the heat loss) for all four days? a. cross ventilation b. stack ventilation c. night insulation of glazing d. none of the above 32. This building's plan is a 50' x 20' rectangle with its long sides about 1/3 glazed. Short sides are unglazed. The bar graphs show the building is oriented with its long sides facing: a. North and South b. East and West c. The building could be oriented with its long walls either East/West or North/South. d. There is insufficient information to answer this question. Use the following energy use reduction strategies to answer questions 33 through 40: I. Solar heating of mass. II. Fixed horizontal overhang shades. III. Cross ventilation. IV. Daylighting. V. Stack ventilation. VI. Night ventilation of mass. VII. Night set-back thermostat. VIII. Fixed vertical fin shades. IX. Fixed egg crate shades. X. Night insulation of glazing. XI. Increased opaque envelope insulation. XII. Low e glazing. XIII. Light colored roof and walls. XIV. Reduced glazing area. XV. Increased glazing area. 33. Which strategies would be effective all day long for all four days: a. I and II Solar heating of mass and horizontal over-hang shading b. III Cross ventilation c. XV Increased glazing area d. XI Increased opaque envelope insulation 34. Which of the following strategies would be most effective in March and December, assuming variable strategies (like night insulation) were used at the correct time of the day? a. I, II, III, IV b. III, IV, V, VI c. I, V, VII, X d. I, II, III, XI 35. Which of the following sets of strategies would be most effective during June and September? a. II, III, VII, IX b. VI, IX, X, XI c. II, IV, XIII, XIV d. VIII, XI, XIII, XIV 36. As shown in the December loads graph total heat gains are roughly equal to heat losses. Which of the following strategies has the potential for producing 0 net load (gain loss = 0) for each HOUR ? a. add mass b. shade c. cross ventilation d. increased envelope insulation 37. Assuming a single zone building with good air mixing, which hour in March has the greatest cooling load? a. 8:00 am 9:00 am b. 9:00 am 10:00 am c. 10:00 am 11:00 am d. 11:00 am noon 38. Assuming a single zone building with good air mixing, which hour in December has the greatest heating load? a. 7:00 am 8:00 am b. 8:00 am 9:00 am c. 9:00 am 10:00 am d. 10:00 am 11:00 am 39. In June which of the following strategies has the potential for producing 0 net load (gain loss = 0) for each HOUR ? a. II, III, XI, XII b. V, IX, XI, XIV c. III, IX, XIII, XIV d. none of the above 40. Which months would have the highest peak load if all the glazing were replaced with opaque wall with the same R value as the rest of the wall in the building and there were no changes in lighting load? a. March and June b. June and December c. September and March d. March and December Questions 41 through 43 require the use of some bar graphs. Click here to view the graphs. The bar graphs represent the performance of the 3 walls shown below in the Phoenix climate.
41. What is the orientation of these walls? a. North b. South c. East d. West 42. Which load graph best matches wall A? a. I b. II c. III d. none of the above 43. Which load graph best matches wall B? a. I b. II c. III d. none of the above Use the following list of energy use reduction strategies to answer questions 44 and 45. I. Use opaque insulating shades. II. Store heat in mass. III. Ventilate (cross or stack) excess heat. IV. Release heat from mass. 44. In a solar heated building, what is the best order that the above strategies should be use in? (Recognizing that this is a diurnal cycle, the starting strategy is not important. What is important is the sequence.) a. III, IV, II, I, III . . . b. II, III, I, IV, II . . . c. II, I, III, IV, II . . . d. III, IV, I, II, III . . . 45. In a mass cooled building, what is the best order that the above strategies should be used in? (Again, remember this is a diurnal cycle.) a. III, IV, II, I, III . . . b. II, III, I, IV, II . . . c. II, I, III, IV, II . . . d. III, IV, I, II, III . . .
46. In the space below, please describe any problems experienced using the WWW interface for the exercises and communication, why you felt the problems arose, and what we might do to solve them. Be as specific as possible.
47. In the space below, please describe what you liked about using the WWW interface. Again, be as specific as possible.
48. In the space below, please comment about using the WWW interface to learn how to use Energy Scheming.
49. In the space below, please comment about using the WWW interface and Energy Scheming to learn about energy and buildings.
When you finish the questions press the button below to submit your answers. IMPORTANT: when you submit the questions for grading, you will be taken to the Final Cooldown. If you are not taken there, there may have been a problem with the automatic grading. If this happens, contact course personnel. The results of your test will be sent to you in an e-mail message:
IMPORTANT: when you submit the questions for grading, you will be taken to the Final Cooldown. If you are not taken there, there may have been a problem with the automatic grading. If this happens, contact course personnel. The results of your test will be sent to you in an e-mail message:
Go to:
Final Exam Cooldown