PPL Aeronautical Knowledge 4

Question 1

What is the standard atmospheric pressure at sea level?

Accepted Answer

1013.2 hPa / 29.92 inHg

Answer

1000 hPa / 30.00 inHg

Answer

1050 hPa / 29.42 inHg

Answer

990 hPa / 28.92 inHg

Question 2

The standard temperature lapse rate in the troposphere is approximately:

Accepted Answer

2°C per 1,000 feet

Answer

1°C per 1,000 feet

Answer

3°C per 1,000 feet

Answer

5°C per 1,000 feet

Question 3

A temperature/dew point spread that is small and decreasing indicates:

Accepted Answer

Increasing likelihood of fog or clouds

Answer

Clear skies ahead

Answer

Rising temperatures

Answer

Strong winds aloft

Question 4

Which type of fog forms on clear nights with light winds due to terrestrial cooling?

Accepted Answer

Radiation fog

Answer

Advection fog

Answer

Upslope fog

Answer

Steam fog

Question 5

The presence of towering cumulus clouds is a sign of:

Accepted Answer

Unstable air with possible turbulence

Answer

Stable air and smooth flying

Answer

An approaching warm front

Answer

High pressure and clear conditions

Question 6

What weather is typically associated with a fast-moving cold front?

Accepted Answer

Squall lines, gusty winds, and possible thunderstorms

Answer

Steady, widespread light rain

Answer

Gradual clearing over many hours

Answer

Persistent fog and drizzle

Question 7

A METAR reporting 'BKN025' means the ceiling is:

Accepted Answer

Broken clouds at 2,500 feet

Answer

Broken clouds at 250 feet

Answer

Broken clouds at 25,000 feet

Answer

Blowing snow at 25 feet