Chapter 6

3381. Every physical process of weather is accompanied by, or is the result of, a

A - Movement of air

B - Pressure Differential

C - Heat Exchange

3382. What causes variations in altimeter settings between weather reporting points?

A - Unequal heating of the Earths surface

B - Variations of terrain elevations

C - Coriolis force

3395.  The wind at 5,000 feet AGL is southwesterky while the surface win is southerly.  This difference in directions is primarily due to

A - stronger pressure gradient at hight altitides.

B - friction between the wind and the surface

C - Stronger Coriolis force at the surface

3450.  COnvection circulation patterns associated with sea breezes are caused by

A - warm, dense air moving inland from over the water.

B - water adsorbing and radiating heat faster than the land.

C - cool, dense air moving inland from over the water.

3383. A temperature inversion would most likely result in which weather condition?

A - Clouds with extensice vertical development above an inversion aloft.

B - Good visibility in the lower levels of the atmosphere and poort visibility above an inversion aloft.

C - An increase in temperature as altitude is increased.

3384.  The most fequent type of ground or surface-based temperature inversion is that wich is produced by

A - terrestrial 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.

3397.  What is meant bu the term "dewpoint"?

A - the temperature at which condensation and evaporation are equal.

B - the temperrature at which dew will always form

C - the temperature to which air must be cooled to become saturated

3398. the amound of water vapor which air can hold depends on the

A - dewpoint

B - air temperature

c - stability of the air

3399.  Clouds, fog, dew will always form when

A - water vapor condenses

B - water vapor is present

C - relative humidity reaches 100 percent

3400.  What are the processes by which moisture is added to unsaturated air?

A - Evaporating and sublimation

B - Heating and condensations

C - Supersaturation and evaporation

3444.  If the temperature/dewpoint spread us small and decreasing, and the temperature is 62 F, what type weather is most likely to develop?

A - Freezing precipitation

B - Thunderstorm

C - Fog or low clouds

3422.  On of the most easily recognized discontitinuities across a front is

A - a change in temperature

B - an increase in cloud coverage

C - an increase in relative humidity

3423.  One weather phenomenon which will always occur when flying across a front is a change in the


A - wind direction

B - type of precipitation

c - stability of the air mass

3385.  Which wather conditions chould be expected beneath a low-level temperature inversion layer when the relative humidity is high?


A - Smotth, air, poor visbility, fog, haze, or low clouds.

B - Light wind shear, poor visibility, haze and light rain.

C - Turbulent air, poor visibility, fog, low stratur type clouds, and showery precipitation

3403.  What measurement can be used to determine the stability of the atmosphere?

A - Atmospheric pressure

B - Actual lapse rate

C - Surface temperature

3404.  What would decrease the stability of an air mass?


A - Warming from below

B - Cooling from below

C - Decrease in water vapor

3405.  What is a characteristic of stable air?

A - Stratiform clouds

B - Unlimited visbility

C - Cumulus clouds

3408.  What feature is associated with a temperature inversion?

A - A stable layer of air

B - An unstable layer of air

C - Chinook winds on mountains slopes

3412.  What are cahracteristic of a moist, unstable air mass?


A - Cumuliform clouds and showery precipitation

B - Poor visibility and smotth air

C - Straitform clouds and showery precipitation

3413.  What are characteristic of unstable air?

A - Turbulence and good surface visibility

B - Turbulence and poor surface visibility

C - Nimbostratus clous and good surface visbility

3414.  A stable air mass is most likely to have which characteristic?


A - Shower precipitation

B - Turbulent air

C - Poor surface visibility

3406.  Moist, stable air flowing upslope can be expected to

A - produce stratus type clouds

B - cause showers and thunderstorms 

C - develop convective turbulence

3407.  If an unstable air mass is forced upward, what type clouds can be expected?

A - Stratus clouds with little vertical development

B - Stratus clouds with considerable associated turbulence.

3424.  Steady precipitation preceding a front is an indication of

A - stratiform clouds with moderate turbulence

B - cumuliform clouds with little or no turbulence

C - stratiform clouds with little or no turbulence

3433.  The conditions necessary for the formation of cumulonimbus clouds are a lifting actions and

A - unstable air containing an excess of condensation nuclei

B - unstable, moist air

C - either stable or unstable air

3409.  What is the approximate base of the cumules clouds id the surface air temperature at 1,000 feet MSL is 70F and the dewpoint is 48F?

A - 4000 feet MSL

B - 5000 feet MSL

C - 6000 feet MSL

3410.  At approximately what altitude above the surface would the pilot expect the base of cumuliform clouds if the surface air temperature is 82F and the dewpoint is 28F?

A - 9,000 feet AGL

B - 10,000 feet AGL

C - 11,000 feet AGL

3415.  The suffix "nimbus", used in naming clouds, means

A - a cloud with extensive vertical development.

B - a rain cloud

C - a middle cloud containing ice pellets

3416.  Clouds are diveded into four families according to their

A - outward shape

B - height range

C - composition

3419.  What clouds have the greates turbulance?

A - Towering cumulus

B - Cumolonimbus

C - Nimbostratus

3417. An almond or lens-shaped cloud which apprears stationary, but which may contain of 50 knots or more, is referred to as

A - an inactive frontal cloud

B - a funnel cloud

C - a lenticular cloud

3418.  Creast of standing mountain waves may be marked by stationary, lens-shaped clouds known as

A - mammatocumulus clouds

B - standing lenticulater clouds

C - roll clouds

3420.  What cloud types would indicate convective turbulence?

A - Cirrus clouds

B - Nimbostratus clouds

C - towering cumulus clouds

3425.  Possible mountain wave turbulance cloud be anticipated when winds of 40 knots or greater blow

A - across a mountain ridge, and the air is stable

B - down a mountain valler, and the air is unstable

C - parallel to a mountain peal, and the air is stable.

3442.  Upon encounterung sever turbulence, which flight condition should the pilot attempt to maintain?

A - Constant altitude and airspeed

B - Constant angle of attack

C - Level flight altitude

3434.  What feature is normally associated with the cumulus stage of a thunderstorm?

A - Roll cloud

B - Continuous updraft

C - Frequent lightning

3235.  Which weather phenomenon signals the beginning of the mature stage of a thunderstorm?

A - The appearance od an anvil top

B - Precipitation beginning to fall

C - Maximum growth rate of the clouds

3439.  What conditiones are necessary for the formation of thunderstorms?

A - High humidity, lifting force, and usntable conditions.

B - High humidity, high temperature, and cumulus clouds.

C - Lifting force, moist air, and extensive cloud cover

3437.  During the life cycle of a thurnderstorm, which stage is characterized predominately by downdrafts?

A - Cumulus

B - Dissipating

C - Mature

3438.  Thunderstorms reach their greatest intensity during  the

A - mature stage

B - downdraft stage

C - cumulus stage

3439.  Thurnderstorms which generally produce the most intense hazard to aircraft are

A - squall line thunderstorms

B - steady-state thunderstorms

C - warm front thunderstorms

3521.  The mature stage of a thunderstorm begins with

A - formation of the anvail top

B - the start of precipitation

C - continous downdrafts

3440.  A nonfrontal, narrow band of active thunderstorms that often develop ahead of a cold front is known as a 

A - prefrontal system

B - squall line

C - dry line

3441.  If there is thunderstorm activity in the vicinity of an airport at which you plan to land, which hazardous atmospheric phenomenon might be expected on the landing approach?

A - Precipitation static

B - Wind-shear turbulence

C - Steady rain

3452.  WHich weather phenomenon is always associated with a thunderstorm?

A - Lightning

B - Heavy rain

C - Hail

3426.  Where does wind shear occur?

A - Only at higher altitudes

B - Only at lower altitudes

C - At all altitudes, in all directions

3427.  When may hazardous wind shear be expected?

A - When stable air crosses a mountain barrier where it tends to flow in layers forming lenticular clouds.

B - In areas of low-level temperatire inversion, frontal zones, and clear air turbulence

C - Following frontal passage when stratocumulus clouds from indicating mechanical mixing

3428.  A pilot can expect a wind-shear zone in a temperature inversion whenever the windspeed at 2,000 to 4,000 feet above the surface is at least

A - 10 knots

B - 15 knots

C - 25 knots

3402.  The presence of ice pellets at the surface is evidence that there

A - are thunderstorms in the area

B - has been cold frontal passage

C - is a temperature inversion with freezing rain at the higher altitude

3429.  One in-flight condition necessary for structurak icing to form is

A - small temperature/dewpoint spread

b - stratiform clouds

C - visible moisture

3430.  In which environment  is aircraft structural ice most likely to have the highest accumulation rate?

A - Cumulus clouds with below freezing temperatures

B - Freezing drizzle

C - Freezing rain

3956.  During a cross-country flight you picked up rime icing which you estimate is 1/2 thick on the leading edge if the wings, you are now below the clouds at 2,000 feet AGL and are approaching your destionation airport under VFR.  Visbility under the clouds is more than 10 miles winds at the destination airport are 8 knots right down the runway, and the sruface temperature is 3C you decide to:

A - use a faster than normal approach and landing speed

B - approach and land at your normal speed since the ice is not thick enough to have any noticeable effect

C - fly your approach slower than normal to lessen the "wind chill" effect and break up the ice.

3443.  What situation is more conducive to the formation radiation fog?

A - Warm, moist air over low, flatland areas on clear, calm nights.

B - Moist, tropical air moving over cold, offshore water.

C - The movement of cold air over much warmer water.

3445. In which situation is advection fog most likely to form?

A - A warm, moist air mass on the windward side of mountains.

B - An air mass moving inland from the coast in winter.

C - A light breeze blowing colder air out of sea

3446.  What types of fog depend upon wind in order to exist?

A - Radiation fog and ice fog

B - Steam fog and ground fog

C - Advection fog and upslope fog

3447.  Low-level turbulence can occur and icing become hazardous in which typer of fog?

A - Rain-induced fog

B - Upslope fog

C - Steam fog

3401.  Which conditions result in the formation of frost?

A - The temperature of the collecting surface is at or below freexing when samll droplets of moisture fall on the surface.

B - The temperature of the collecting surface is at or below the dewpoint od the adjacent air and the dewpoint is below freezing

C - The temperature of the surrounding air is at or below freezing when small drops of moisture fall on the collecting surface

3432.  How does frost effect the lifting surface of an  airplane on takeoff?


A - Front may prevent the airplane from becoming airborne at normal takeoff speed

B - Frost will change the camber of the wind increasing lift during takeoff

C - Frost amy cause the airplce to become airborn with a lower angle of attack at a lower indicated airspeed.

3206.  How will frost in the winds of an airplane affect takeoff performance?

A - Frost will discrupt the smooth flow of air over the wind, adversely affecting its lifting capability.

B - Frost will change the camber of the wing, increasing its lifting capability.

C - Frost will cause the airplace to beceom airbornse with a higher angle of attach, decreasing the stall speed.

3431.  Why si sfrost considered hazardous to flight?

A - Frost changes the basic aerodynamic shape of the airfoils, thereby increasing lift.

B - Frost slows the airflow over the airfoils, thereby increasing control effectiveness.

C - Frost spoils the smooth flow of air over the wings, thereby decreasing lifting capability.