Arch Sci Exam 1

True/False: a lesson learned from “Easter Island” is that population and development may increase indefinitely without causing serious damage to the environment.

False

True/False: Energy in the sun is generated by nuclear fusion between hydrogen atoms to generate Helium, which means that the sun will keep its mass unchanged over time

False

True/False: The Earth orbits around the sun counterclockwise , and rotates around its own axis counterclockwise (North is up)

True

True/False: In the Southern Hemisphere, Summer occurs when earth is at its closest point to the sun on June 21st

False

True/False: At the Equator, the sun is strongest (exactly overhead) on the two equinoxes, March 21st and September 21st

True

True/False: At any location at solar noon on the two equinoxes; the vertical sun angle (altitude) is equal to the latitude of the location.

False

True/False: The sky looks blue because the scattered light in the atmosphere is dominated by the blue wavelength.

True

True/False: The Psychrometric Chart can be used to determine several psychrometric properties of moist air when at least any two properties (related or unrelated) properties are known

False

True/False: Latent heat cannot be measured by a regular (dry-bulb) thermometer.

True

True/False: At the same location, the magnetic declination angle (angle between magnetic and true north) does not change over time

False

True/False: When moist air is cooled down, its dry-bulb temperature drops down. In this cooling process, its relative humidity also drops down.

False

True/False: Equal (thermal) comfort is a result of an equal rate of heat loss to the environment regardless of the mechanism through which the body losses heat.

True

Humans environmental impact on the planet is a function of:

• Population

• Affluence per capita

• Technology

Quality of life correlates with energy consumption per capita. One indication of that is:

Rate of illiteracy decrease with increased use of energy

At a location that is at 30 degrees NL, at solar noon on the two equinoxes , the solar altitude is:

60 degrees

At which location are all days divided, year-round, equally between day and night:

The Equator

At a specific site in a downtown area, which level of climate affects the performance of buildings

Micro climate

When does the human body feel satisfied with the thermal environment?

When it loses equal amount of heat to what generates

When does the human body lose more heat through convection and radiation than through evaporation?

Lower temperatures (lower than. 80 degrees F)

Which comfort indicator shows the combined effect of temperature and humidity?

Effective temperature and heat index

On a cold winter night and in a highly glazed perimeter space, do you expect that the Mean radiant temperature (MRT) to be:

Lower than room temperature

On the psychometric chart, at which condition is the wet bulb temperatures of moist air equal to its dry bulb temperatures

• at the saturation level

• At the dewpoint temperature

• 100% relative humidity

True/False: The energy in the sun is generated by nuclear fusion between Hydrogen atoms to generate Helium which means that the sun will keep its mass unchanged indefinitely

False, the mass slowly decreases with time A

True/False: All solar radiation received at the outer atmosphere is also received at sea level (same intensity of radiant heat)

False, intensity @ seas level is lower

True/False: In the Northern Hemisphere, the summer happens when the earth is closest to the sun

False, Earth is actually further from the sun at this point, but titled toward the sun

True/False: The Psychrometric Chart can be used to study Human Thermal Comfort, as well as the indoor and outdoor environmental conditions. Using the chart, it is possible to determine several thermal properties of moist air when at least any two (unrelated) properties are known.

True, when moist air cools, relative humidity increases (constant humidity ratio)

True/False: Equal (thermal) comfort is a result of equal rate of heat loss to the environment.

True

True/False: According to ASHRAE, thermal comfort is defined as the “condition of mind which expresses satisfaction with the thermal environment.

True

True/False: Latent heat cannot be measured by a regular (dry-bulb) thermometer.

True, latent heat does not change air temperature directly

ASHRAE stands for ________

American Society of heating, Refrigerating, and AC Engineers

The six factors that affect human comfort include four environmental factors which are________, and two personal factors, which are ______

1. Air Temperature

2. Humidity (RH)

3. Air Velocity

4. Mean Radiant Temperature (MRT, temperature of surrounding surfaces)

1. Metabolic Rate (Level of activity)

2. Clothing Insulation (Amount)

Define Wind Chill Factor

The perceived decreased in air temperature felt by the body due to the combined effect of cold air and wind speed

For moist-air, define “Dew Point”

The temperature at which air becomes saturated with water vapor and condensation begins. Dry bulb temperature is lowered.

In terms of equal comfort, which comfort indicator shows the combined effect of DB temperature and radiation (MRT)

Operative Temperature

When does the human body lose more heat through evaporation than through convection and radiation?

Higher Temperature (higher than 80 degrees Fahrenheit)

When does the human body feel satisfied with the environment?

When it loses the same amount of heat it generates

In spaces with physical activity that is heavier than normal (such as in a gymnasium),

A. Thermostat should be adjusted to a lower temperature than normal

B. Thermostats should be adjusted to a high temperature than normal

A. Thermostat should be adjusted to a lower temperature than normal

On the psychrometric chart, at which condition does the wet-bulb temperature of moist-air equal its dry bulb temperature?

A. At the saturation level

B. At the dew point temperature

C. A 100% relative humidity

D. Any of the above

D. Any of the above

In the winter of the Northern Hemisphere (December 21st), where does the day become 24 hours of darkness (sun is below the Horizon)?

Location at higher latitude than 66.5-degrees NL (north of the polar circle)

When do the Northern and Southern Hemispheres receive equal amounts of solar radiation

A. March 21st

B. June 21st

C. September 21st

D. December 21st

E. A and C only

F. B and D only

E. A and C only (equinox)

At a location that is at 40 degrees NL, at solar noon in summer (June 21st), solar altitude is:

SA = 90 - 40 = 50

50 + 23.5 (June 21) = 73.5

73.5 Degrees

In a dry-air condition, the psychrometer will read a wet-bulb temperature that is …

A. Equal to the dry-bulb temperature

B. Higher than the dry-bulb temperature

C. Lower than the dry-bulb temperature

C. Lower than the dry-bulb temperature

The DB (dry-bulb) temperature in a room is 75 degrees Fahrenheit, however occupants feel cold. The reason is probably….

A. Lower relative humidity than 50%

B. High air movement

C. Colder Surfaces (glass) inside the room

D. Any of the above

D. Any of the above