Random1 Flashcards
What happens to latent heat when water vapour changes to water, or water changes to ice?
Latent heat is released.
What is “dew point”?
It is the temperature at which the air becomes fully saturated with water.
The dew point is the temperature at which a given sample of air will have a relative humidity of 100 percent
What is “Dew point temperature”?
Dew point temperature is defined as the temperature to which the air would have to cool (at constant pressure and constant water vapor content) in order to reach saturation.
What is saturation?
The limit to the amount of water vapour the air at a given temperature can hold.
Station A has an air temperature of 33°C and a dew point of 32°C and Station B has an air temperature 29°C and a dew point of 23°C.
Which of the above station would more likely have a higher Relative Humidity?
What are four main causes of turbulence?
1) Convection currents.
2) Obstructions to wind flow.
3) Wind shear.
4) Wing tip vortices.
What gases make up the atmosphere?
• Nitrogen 78%
• Oxygen account 21%
• Argon, carbon dioxide, helium, neon and other gases make up the remaining 1%.
What is “ISA”?
International Standard Atmosphere (ISA) is a model used for the standardization of aircraft instruments.
What is the name of the instrument used for measuring atmospheric pressure ?
A Barometer.
What is Atmospheric Pressure?
(a) The Density of the air.
(b) The weight of force of the atmosphere on a specific surface area. (c) The movement of air from place to place.
b.
What is ICAO’s standard atmosphere?
Height (km) = 0 km MSL
Temperature = 15.0 °C
Pressure hpa = 1013.25
Lapse rate °C/1000 ft = −1.98
Air density kg/m3 = 1.225
Humidity, also called relative humidity, refers to the amount of water vapour contained in the atmosphere. True or False?
True.
Water vapour is heavier than air. True or false ?
False. Water vapour is lighter than air; consequently, moist air is lighter than dry air.
How is humidity measured?
With a hygrometer.
Common type uses dry and wet bulb thermometers.
What is relative humidity?
Relative Humidity is the percentage degree of saturation. It is the ratio of the amount of water vapour in the air to the amount which the air could hold at the same temperature if it were saturated.
