Book 2 Chapter 1: Heat Gains & Losses Flashcards
External heat gains include those by:
A) Infiltration
B) Ventilation
C) Solar radiation
D) All of the above
D) All of the above
A wind velocity of __________ is used to calculate the winter infiltration heat losses.
A) 24km/hr (15mph)
B) 15km/hr (9.4mph)
C) 30km/hr (18.8mph)
D) 36km/hr (22.5mph)
A) 24km/hr (15mph)
The heat given off by light fixtures is not greatly affected by the:
A) Current flow
B) Room temperature
C) Wind speed
D) Ambient temperature
B) Room temperature
Heat losses through large, single pane window sections are _______________ double pane windows, which have the space between the panes filled with argon.
A) Significantly less than
B) Approximately the same as
C) Significantly greater than
D) Marginally greater than
C) Significantly greater than
The amount of heat lost by conduction, convection, radiation,and infiltration is directly affected by the:
A) Room temperature
B) Room size
C) Ambient temperature
D) Wind velocity
D) Wind velocity
External heat gains in a building are caused by:
A) Hot water tanks, boilers, and appliances
B) Exhausted air, radiation through windows, lighting
C) Motors, boilers, and other mechanical equipment
D) Infiltration, conduction, ventilation and solar radiation
E) Infiltration and heat gain from people and lighting
D) Infiltration, conduction, ventilation and solar radiation
Which of the following methods can be used to estimate the ventilation load on a building?
A) Conversion method
B) The “U” factor method
C) Ventilation method
D) Conduction method
E) Crack method
E) Crack method
Thermal conductance (C) may be defined as the:
A) Thermal transmission through a unit of a particular body where the difference between temperatures on either side of the body is unity (W/m2K)
B) Thermal heat flow by conduction only through a single uniform type of material (W/mK)
C) Thermal heat flow through a unit of a non-uniform composite material when a unit average temperature difference is established between the surfaces (W/m2K)
D) Reciprocal of thermal conductance (mK/W)
E) Quality of heat flow in unit time (Q or W)
C) Thermal heat flow through a unit of a non-uniform composite material when a unit average temperature difference is established between the surfaces (W/m2K)
Heat load from the people in a room is mostly affected by:
A) The number of people
B) The size of the people
C) None of the above
D) The activity of the people
E) Smoking
D) The activity of the people
One of the factors used to determine the ventilation rate in a building is the:
A) Cubic metre per hour (CFM) requirements per person
B) Solar load on a building
C) Type of electrical equipment used in the building
D) Activity in the building
E) Type of insulation used in the building
A) Cubic metre per hour (CFM) requirements per person
The resistance to heat flow through walls, floors, and windows is known as:
A) U-factor
B) Ventilation
C) Infiltration
D) Total thermal resistance
E) Reduced solar load
A) U-factor
Electric motors give off _________ while running.
A) Solar heat
B) No heat to the atmosphere
C) Latent and sensible heat
D) Sensible heat
E) Latent heat
D) Sensible heat
Heat loss from a building is:
A) Affected by wind velocity
B) Is not affected by wind velocity
C) Independent from the outside air temperature
D) Dependant on the shape of the openings in a building
E) Not affected by the density of the air
A) Affected by wind velocity
Rankine and Kelvin are absolute temperature scales whose starting point is absolute zero (the lowest temperature possible). They are related to Fahrenheit and Celsius temperature scales by:
A) C=Kelvin -460, F=Rankine +273
B) C=Rankine -273, F=Kelvin -460
C) C=Kelvin -273, F=Rankine -460
D) C=Rankine -460, F=Kelvin -273
E) C=Kelvin 460, F=Rankine -273
C) C=Kelvin -273, F=Rankine -460
The amount of heat lost by a building due to conduction, convection, and infiltration is directly affected by:
A) The velocity of the wind
B) Outside air temperature
C) The type of heating system used in the building
D) The type of activity in the building
E) Geographic location of the building
A) The velocity of the wind
Rankine and Kelvin are absolute temperature scales whose starting point is absolute zero (the lowest temperature possible). Fahrenheit = Rankine - 460. (Zero R=460F, or, freezing point of water =+ 32 degrees Fahrenheit =+492 Rankine) If Celsius = Kelvin -273, zero K =273C, then boiling point of water =:
A) 560K and 485R
B) 273K and 460R
C) 373K and 672R
D) 173K and 248R
E) 100K and 212R
C) 373K ad 672R
Heat energy always moves from:
A) A cooler source to a warmer source
B) Higher levels to lower levels
C) Lower levels to higher levels
D) Outside to inside
E) A warmer source to a cooler source
E) A warmer source to a cooler source
Building heat losses can be related to a large extent by adding a layer, or layers, of:
A) Building wrap
B) Wall paper
C) Paint
D) Glass
E) Insulation
E) Insulation
Conduction heat gains are based on the assumption that the temperature of the outer surface of the building is the same as the:
A) Outdoor design
B) Coldest winter temperature
C) Indoor design temperature
D) Warmest summer temperature
E) Average of winter and summer temperatures
A) Outdoor design
Heat passes through building walls, ceilings, and floors from the warmer inner surfaces to the cooler outer surfaces by:
A) Insulation
B) Construction
C) Conduction
D) Conservation
E) Occupation
C) Conduction
Building air infiltration should be kept to a minimum a certain amount of fresh air is required to provide _________ within the building.
A) Ventilation
B) Cooling
C) Humidification
D) Dust control
E) Heating
A) Ventilation
The force of air into a building by means of fans is called.
A) Ventilation
B) Infiltration
C) Occupation
D) Radiation
E) Convection
A) Ventilation
Thermal resistance (R) is the:
A) Thermal heat flow through a unit area of a non-uniform, composite material when a unit average temperature difference is established between the surfaces (W/m2ºC)(Btu/hr/ft2ºF)
B) Quantity of heat flow from all mechanism,in unit time, under the conditions prevailing that time (Q or W)
C) Reciprocal of thermal conductance, it is the value of a given material’s ability to resist heat transfer or flow (m2C/W) (ft2/Btu/hr)
D) Thermal heat flow (transmission) through unit areas of a wall, door, window, etc., for every degree temperature difference between the air/fluid inside and the air/fluid outside. (W/m2K or W/m2C) (Btu/hr/ft2R or Btu/hr/ft2F)
E) Thermal heat flow, by conduction only, through a unit area of a single uniform type material (W/mºC) (Btu/hr/ft2F)
C) Reciprocal of thermal conductance,it is the value of a given material’s ability to resist heat transfer or flow (m2C/W) (ft2/Btu/hr)
One of the ways that heat is transmitted is by:
A) Occupation
B) Convection
C) Conservation
D) Construction
E) Insulation
B) Convection
The wind velocity used to calculate summer infiltration heat gains is:
A) 15 km/h (9.3mph)
B) 24 km/h (14.9mph)
C) 12 km/h (7.5mph)
D) 20 km/h (12.4mph)
E) 10km/h (6.2mph)
C) 12 km/h (7.5mph)
The amount of heat lost by conduction, convection, radiation,and infiltration is directly affected by the:
A) Room size
B) Wind velocity
C) Room temperature
D) Ambient temperature
E) Angle of the sun
B) Wind velocity
