Causes of Weather
The primary cause of all changes in the Earth’s weather is
A. variation of solar energy received by the Earth’s regions.
B. changes in air pressure over the Earth’s surface.
C. movement of the air masses.
A. variation of solar energy received by the Earth’s regions.
An air mass is a body of air that
A. has similar cloud formations associated with it.
B. creates a wind shift as it moves across the Earth’s surface.
C. covers an extensive area and has fairly uniform properties of temperature and moisture.
C. covers an extensive area and has fairly uniform properties of temperature and moisture.
What is an indication that downdrafts have developed and the thunderstorm cell has entered the mature stage?
A. The anvil top has completed its development.
B. Precipitation begins to fall from the cloud base.
C. A gust front forms.
B. Precipitation begins to fall from the cloud base.
Which conditions are favorable for the formation of radiation fog?
A. Moist air moving over colder ground or water.
B. Cloudy sky and a light wind moving saturated warm air over a cool surface.
C. Clear sky, little or no wind, small temperature/dew point spread, and over a land surface.
C. Clear sky, little or no wind, small temperature/dew point spread, and over a land surface.
If the air temperature is +8°C at an elevation of 1,350 feet and a standard (average) temperature lapse rate exists, what will be the approximate freezing level?
A. 3,350 feet MSL.
B. 5,350 feet MSL.
C. 9,350 feet MSL.
B. 5,350 feet MSL.
Which force, in the Northern Hemisphere, acts at a right angle to the wind and deflects it to the right until parallel to the isobars?
A. Centrifugal.
B. Pressure gradient.
C. Coriolis.
C. Coriolis.
What are the characteristics of stable air?
A. Good visibility, steady precipitation, and stratus-type clouds.
B. Poor visibility, intermittent precipitation, and cumulus-type clouds.
C. Poor visibility, steady precipitation, and stratus-type clouds.
C. Poor visibility, steady precipitation, and stratus-type clouds.
Which procedure is recommended if a pilot should unintentionally penetrate embedded thunderstorm activity?
A. Reverse aircraft heading or proceed toward an area of known VFR conditions.
B. Reduce airspeed to maneuvering speed and maintain a constant altitude.
C. Set power for recommended turbulence penetration airspeed and attempt to maintain a level flight attitude.
C. Set power for recommended turbulence penetration airspeed and attempt to maintain a level flight attitude.
The most frequent type of ground- or surface-based temperature inversion is that produced by
A. radiation on a clear, relatively still night.
B. warm air being lifted rapidly aloft in the vicinity of mountainous terrain.
C. the movement of colder air under warm air, or the movement of warm air over cold air.
A. radiation on a clear, relatively still night.
On which surface of the aircraft could a pilot generally expect to see the first sign of ice accumulation?
A. Pitot tube.
B. Wing.
C. Propeller.
A. Pitot tube.
Winds at 5,000 feet AGL on a particular flight are southwesterly while most of the surface winds are southerly. This difference in direction is primarily due to
A. a stronger pressure gradient at higher altitudes.
B. friction between the wind and the surface.
C. stronger Coriolis force at the surface.
B. friction between the wind and the surface.
What type clouds can be expected when an unstable air mass is forced to ascend a mountain slope?
A. Layered clouds with little vertical development.
B. Stratified clouds with considerable associated turbulence.
C. Clouds with extensive vertical development.
C. Clouds with extensive vertical development.
During the life cycle of a thunderstorm, which stage is characterized predominantly by downdrafts?
A. Cumulus.
B. Dissipating.
C. Mature.
B. Dissipating.
Fog is usually prevalent in industrial areas because of
A. atmospheric stabilization around cities.
B. an abundance of condensation nuclei from combustion products.
C. increased temperatures due to industrial heating.
B. an abundance of condensation nuclei from combustion products.
In which meteorological environment is aircraft structural icing most likely to have the highest rate of accumulation?
A. Cumulonimbus clouds.
B. High humidity and freezing temperature.
C. Freezing rain.
C. Freezing rain.
A characteristic of the stratosphere is
A. an overall decrease of temperature with an increase in altitude.
B. a relatively even base altitude of approximately 35,000 feet.
C. relatively small changes in temperature with an increase in altitude.
C. relatively small changes in temperature with an increase in altitude.
What enhances the growth rate of precipitation?
A. Advective action.
B. Upward currents.
C. Cyclonic movement.
B. Upward currents.
When approaching a cumulonimbus cell that is on your route of flight, a pilot should
A. circumnavigate the cell by at least 20 nautical miles.
B. descend to an altitude that will allow the aircraft to fly under the cell.
C. fly under the anvil to protect the aircraft from violent parts of the cell.
A. circumnavigate the cell by at least 20 nautical miles.
Penetrating fog while flying an approach at night, you might experience the illusion of
A. pitching up.
B. flying at a lower altitude.
C. constant turning.
A. pitching up.
Test data indicate that ice, snow, or frost having a thickness and roughness similar to medium or coarse sandpaper on the leading edge and upper surface of an airfoil can
A. reduce lift by as much as 50 percent and increase drag by as much as 50 percent.
B. increase drag and reduce lift by as much as 25 percent.
C. reduce lift by as much as 30 percent and increase drag by 40 percent.
C. reduce lift by as much as 30 percent and increase drag by 40 percent.
Which feature is associated with the tropopause?
A. Absence of wind and turbulent conditions.
B. Absolute upper limit of cloud formation.
C. Abrupt change in temperature lapse rate.
C. Abrupt change in temperature lapse rate.
Stability can be determined from which measurement of the atmosphere?
A. Low-level winds.
B. Ambient lapse rate.
C. Atmospheric pressure.
B. Ambient lapse rate
What are the requirements for the formation of a thunderstorm?
A. A cumulus cloud with sufficient moisture.
B. A cumulus cloud with sufficient moisture and an inverted lapse rate.
C. Sufficient moisture, an unstable lapse rate, and a lifting action.
C. Sufficient moisture, an unstable lapse rate, and a lifting action.
The amount of water vapor which air can hold largely depends on
A. relative humidity.
B. air temperature.
C. stability of air.
B. air temperature.
The most susceptible surface of the aircraft for ice accumulation is the
A. windshield.
B. main wing.
C. tailplane.
C. tailplane.