Chapter 4 & 5

The U.S. Department of Energy's climate zones are based on the exterior air temperature. the exterior humidity. precipitation. (a) and (b). (b) and (c).

(a) and (b).

Which of the following insulating materials contain HCFC gas within their voids? Extruded polystyrene Polyisocyanurate Polyurethane All of the above Only (b) and (c)

All of the above

A building assembly with a higher U-value is thermally more insulating than one with a lower U-value. True False

False

IECC is an acronym for Institute for Energy Conversion and Conservation. Institute for Energy Conservation and Codification. International Energy Conservation Code. International Energy Cooperation Council. none of the above.

International Energy Conservation Code.

The unit for the measure of energy in the SI system of units is calorie. Joule. Btu. Watt.

Joule.

The R-value of a 1-in.-thick extruded polystyrene board is 5.0. If the R-value of a 1-in.-thick brick wall is 0.2, how thick should the brick wall be to equal the R-value of 1-in.-thick extruded polystyrene? 10 in. 5 in. 50 in. 2.5 in. None of the above

None of the above

In a suspension bridge, which member(s) is (are) in compression? Suspension cable Hanger cables Support pylons Both suspension cable and hanger cables None of the above

Support pylons

A concrete slab-on-ground does not require to be insulated in warm climates. True False

True

In a typical stress-strain diagram of a material, the stress is generally plotted along the vertical axis. True False

True

When a cable or rope is compressed by a force, what is the compressive stress in it? Equal to the force applied Force divided by the cross-sectional area of rope Zero Infinite None of the above

Zero

The F-factor relates to heat flow through glazed wall. above-ground opaque wall. basement wall. a concrete roof slab. a concrete slab-on-ground.

a concrete slab-on-ground.

Apart from the climate of the location, the other factors that affect energy-conscious building design are building orientation and building shape. building envelope. site conditions. all of the above. (a) and (b).

all of the above.

The unit of modulus of elasticity is psi. ksi. Pa. GPa. all of the above.

all of the above.

Concrete is an elastic material. a plastic material. an elastic-plastic material. none of the above.

an elastic material.

Low-carbon (mild) steel is an elastic material. a plastic material. an elastic-plastic material. none of the above.

an elastic-plastic material.

For energy conservation, materials with high thermal mass are effective in climates in which the heat flow through the building envelope is bidirectional within a 24-h period during a large part of the year. unidirectional within a 24-h period during a large part of the year. absent during a large part of the year.

bidirectional within a 24-h period during a large part of the year.

Within an air space (cavity), the mode of heat transfer is primarily by conduction. convection. radiation. both (a) and (b). both (b) and (c).

both (b) and (c).

The horizontal blocking in wood studs helps prevent compressive failure of studs. shear failure of studs. tensile failure of studs. buckling of studs.

buckling of studs.

The material in an arch is primarily in compression. tension. both tension and compression. shear. none of the above.

compression

The bearing strength of a material is closely related to its bending strength. tensile strength. compressive strength. modulus of elasticity. none of the above.

compressive strength.

Within a solid, the mode of heat transfer is by conduction. convection. radiation. both (a) and (b). both (b) and (c).

conduction

The test specimen used for determining the compressive strength of concrete in the United States is a cube measuring 12 in.×12 in.×12 in. cube measuring 6 in.×6 in.×6 in. prism measuring 6 in.×6 in.×12 in. cylinder measuring 12 in.in diameter×6 in.high. cylinder measuring 6 in.in diameter×12 in.high.

cylinder measuring 6 in.in diameter×12 in.high.

In a simple three-member truss consisting of two rafters and a tie, each member is in compression. tension. either tension or compression. shear. both tension and compression.

either tension or compression.

The concept of aged R-value is applicable to all insulating materials. insulating materials that contain HCFC gas. fiberglass insulation. perlite board insulation. all building materials.

insulating materials that contain HCFC gas.

Foamed concrete is generally used as insulation in walls. steep roofs. foundations. all of the above. none of the above.

none of the above.

Insulation is most effective if it is placed on the outside face of the assembly. on the inside face of the assembly. in the center of the assembly.

on the outside face of the assembly.

The bending stresses along the neutral axis of a beam are minimum. maximum. zero. none of the above.

zero

The U-value and R-value of an assembly are related to each other by which relationship? U=R U+R=1 (U)(R)=1.0 U2+R2=1.0 None of the above

(U)(R)=1.0

The emissivity of a material lies between 0 and 1. 1 and 2. 1 and 10. 0 and 100. none of the above.

0 and 1.

The R-value of a single glass sheet, without considering the film resistances, is approximately 4.0. 3.0. 2.0. 1.0. 0.

0.

A 20-ft-high column shortens by 0.6 in. under a load. What is the resulting strain in the column? 0.0020 0.0020 in. 0.0025 in. 0.0025 None of the above

0.0025

A wall framed with wood or steel studs is a mass wall. True False

False

The R-value of a building assembly is influenced by the inside and outside air films. The sum of the R-values of these two films (Rsi+Rso) is approximately equal to 0.1. 5.0. 10.0. 1.0. none of the above.

1.0.

The R-value of a single glass sheet, including the film resistances, is approximately 4.0. 3.0. 2.0. 1.0. 0.

1.0.

A rectangular column measuring 12 in.×12 in. in cross section carries a load of 18 kips. What is the stress in the column? 18 kips 18 ksi 2.25 ksi None of the above 125 psi

125 psi

Which gives greater warning before failure? A brittle material A ductile material

A ductile material

Which of the following steel stud wall assemblies gives a higher overall R-value? In both assemblies, the total amount of insulation is R-15. Assembly A has an exterior insulating sheathing of R-5 and within-stud insulation of R-10 Assembly B has an exterior insulating sheathing of R-3 and within-stud insulation of R-12

Assembly A has an exterior insulating sheathing of R-5 and within-stud insulation of R-10

In which of the following locations is blown-in insulation most commonly used? Stud wall cavities Masonry wall cavities Top of a flat roof Attic spaces

Attic spaces

The unit for the measure of energy in the U.S. system of units is calorie. Joule. Btu. Watt-hour. all of the above.

Btu.

In which of the following buildings will heat flow occur unidirectionally? Continuously heated or cooled buildings Intermittently heated buildings Intermittently cooled buildings All of the above None of the above

Continuously heated or cooled buildings

Which of the following plastic foam insulation contains air within its voids? Extruded polystyrene (XPS) board Expanded polystyrene (EPS) board (bead board) Polyisocyanurate board (ISO board)

Expanded polystyrene (EPS) board (bead board)

Which of the following insulating materials is available in the form of rigid boards? Fiberglass Rock wool Insulating concrete Extruded polystyrene None of the above

Extruded polystyrene

Which of the following insulations is combustible? Fiberglass Foamed concrete Perlite board Extruded polystyrene (XPS) board Vermiculite

Extruded polystyrene (XPS) board

A wet or moist material provides a higher R-value than if the same material is dry. True False

False

Air is a good thermal insulator, provided that it exists in large volumes. True False

False

In climates where a concrete slab-on-ground must be insulated, it should be insulated under its entire area. True False

False

In most materials, the safety margin for compressive stress and bending stress is the same. True False

False

The walls of a conditioned basement must be insulated over the entire depth of the wall. True False

False

Which of the following insulating materials is available in the form of batts? Fiberglass Expanded perlite Insulating concrete Extruded polystyrene None of the above

Fiberglass

For the same thickness, which of the following materials has the smallest R-value? Extruded polystyrene Expanded polystyrene Polyisocyanurate Fiberglass Gypsum

Gypsum

Which of the following materials has the smallest value of emissivity? Fiberglass Highly compressed fiberglass Metal Highly polished metal All of the above have the same value of emissivity

Highly polished metal

Which of the following beam cross sections is structurally more efficient in bending? Rectangular (solid) section I-section

I-section

The R-value of a 2-in.-thick material is 4.0. What is the R-value of the same material if its thickness is 1 in.? 1.0 0.5 6.0 8.0 None of the above (2.0)

None of the above (2.0)

What is the yield stress of grade 60 reinforcing steel? 60 lb 6,000 lb 6,000 psi 60 psi None of the above (60 ksi)

None of the above (60 ksi)

For the same thickness, which of the following materials has the highest R-value? Extruded polystyrene Expanded polystyrene Polyisocyanurate Fiberglass Gypsum

Polyisocyanurate

The approximate R-value of an air space in a wall is R-1. R-1.5. R-2.0. R-2.5. none of the above.

R-1.

The approximate R-value of an air space in a wall with an aluminum foil lining is R-1. R-1.5. R-2.0. R-2.5. none of the above.

R-2.5.

A wall assembly ( total area=100 ft2) consists of 80 ft2 of opaque wall with an R-value of R-20 and a 20 ft2 of window whose R-value is R-2. The effective (overall) R-value of the entire wall assembly is approximately R-15. R-11. R-7. R-3. none of the above.

R-7.

The R-value of a building assembly in the SI system is referred to as the R-value (SI). SI-value. RS-value. RSI-value. none of the above.

RSI-value.

Insulating materials that contain HCFC gas within their cells have a higher R-value than those that contain air within their cells. True False

True

Like color, emissivity is a property of the surface of the material, not of the entire body of the material. True False

True

The primary purpose of longitudinal steel bars in a reinforced concrete beam is to overcome the weakness of concrete in tension. True False

True

The stress-strain diagram of mild steel is nearly a straight line up to the yield point. True False

True

The units of measurement of U-value and U-factor are the same. True False

True

The use of aluminum foil in attics is more useful in warm climates than in cold climates. True False

True

Which of the following beam cross sections is structurally more efficient in bending? Rectangular (solid) section Tubular section

Tubular section

In a steel column that rests on a concrete footing, the area of the bearing plate used is generally greater than the cross-sectional area of the column. equal to the cross-sectional area of the column. smaller than the cross-sectional area of the column.

greater than the cross-sectional area of the column.

The stirrups in a reinforced concrete beam are used to increase the strength of the beam in bending. reduce the deflection of the beam. increase the durability of the beam. increase the strength of the beam in shear. none of the above.

increase the strength of the beam in shear.

When an aluminum foil is used in attic spaces, it is laminated to ceiling gypsum board. laminated to fiberglass insulation. sandwiched between ceiling gypsum board and fiberglass insulation. laminated to outside-facing surface of roof sheathing. laminated to inside-facing surface of roof sheathing.

laminated to inside-facing surface of roof sheathing.

The allowable stress in a material is generally equal to its ultimate stress. less than its ultimate stress. greater than its ultimate stress. none of the above.

less than its ultimate stress.

Aluminum foil is commonly used in building assemblies because it lowers heat transfer due to conduction. lowers heat transfer due to convection. lowers heat transfer due to radiation. lowers heat transfer due to conduction as well as convection. lowers heat transfer due to convection as well as radiation.

lowers heat transfer due to radiation.

In relation to its compressive strength, the tensile strength of concrete is much higher. slightly higher. nearly the same. much lower. slightly lower.

much lower.

One of the main reasons for using HCFC gas in some insulating materials is that it makes the material noncombustible. makes the material more economical. makes the material more resistant to decay. increases the strength of the material. none of the above.

none of the above.

The coastal region of the western United States lies in climate zone 1(A). climate zone 2(A). climate zone 3(A). climate zone 4(A). none of the above.

none of the above.

The primary purpose of ties in a reinforced concrete column is to prevent the buckling of vertical reinforcement in the column. prevent the crushing of concrete. increase the shear resistance of the column. none of the above.

prevent the buckling of vertical reinforcement in the column.

Modulus of elasticity refers to how strong a material is. stiff a material is. elastic a material is. serviceable a material is. none of the above.

stiff a material is.

The International Energy Conservation Code provides two alternative paths of compliance. three alternative paths of compliance. four alternative paths of compliance. five alternative paths of compliance. none of the above.

three alternative paths of compliance.

When we determine the strength of concrete using the test specimens, we determine the concrete's ultimate compressive stress. ultimate tensile stress. ultimate shear stress. modulus of elasticity. all of the above.

ultimate compressive stress.

A material that is weak in tension is strong in bending. weak in bending. no relationship between the tensile and bending strengths of a material.

weak in bending.

A material that is weak in tension strong in shear. weak in shear. no relationship between the shear and tensile strengths of a material.

weak in shear.