DGCA Meteorology: Air Density Questions

21 exam-style Air Density questions for the DGCA Meteorologypaper (CPL & ATPL). The first 12 are free below with answers and explanations — sign up free to practise all of them with progress tracking.

  1. Q1

    Density is _____ at poles than equator

    • ALower
    • BHigher
    • CSame
    Show answer

    Correct answer: B. Higher

    Air density at the surface is higher at the poles than at the equator because polar air is much colder, and colder air at comparable pressure is denser.

  2. Q2

    Consider the following statements relative to Air Density and select the one which is correct:

    • ABecause air density increases with decrease of temperature, air density must increase with increase of height in the International Standard Atmosphere (ISA..
    • BAt any given surface temperature the air density will be greater in anticyclonic conditions than it will be when the MSL pressure is lower.
    • CAir density increases with increase of relative humidity.
    • DThe effect of change of temperature on the air density is much greater than the effect of change of atmospheric pressure
    Show answer

    Correct answer: B. At any given surface temperature the air density will be greater in anticyclonic conditions than it will be when the MSL pressure is lower.

    This Explanation is Coming Soon

  3. Q3

    The tropopause in mid latitudes is:

    • ALower in summer with a lower temperature.
    • BLower in winter with a higher temperature.
    • CLower in summer with a higher temperature.
    • DLower in winter with a lower temperature.
    Show answer

    Correct answer: B. Lower in winter with a higher temperature.

    This Explanation is Coming Soon

  4. Q4

    Generally as altitude increases:

    • Atemperature decreases and density increases
    • Btemperature, pressure and density decreases
    • Ctemperature and pressure increase and density decreases
    • Dtemperature decreases and pressure density increases
    Show answer

    Correct answer: B. temperature, pressure and density decreases

    This Explanation is Coming Soon

  5. Q5

    In the troposphere:

    • Aover cold air, the pressure is higher at upper levels than at similar levels over warm air
    • Bover cold air, the pressure is lower at upper levels than at similar levels over warm air
    • Cover warm air, the pressure is lower at upper levels than at similar levels over warm air
    • Dthe upper level pressure depends solely on the relative humidity below
    Show answer

    Correct answer: B. over cold air, the pressure is lower at upper levels than at similar levels over warm air

    This Explanation is Coming Soon

  6. Q6

    Density at the surface will be low when:

    • APressure is high and temperature is high.
    • BPressure is high and temperature is low.
    • CPressure is low and temperature is low.
    • DPressure is low and temperature is high.
    Show answer

    Correct answer: D. Pressure is low and temperature is high.

    This Explanation is Coming Soon

  7. Q7

    At FL 180, the air temperature is -35°C.The air density at this level is:

    • AEqual to the density of the ISA atmosphere at FL 180.
    • BUnable to be determined without knowing the QNH.
    • CGreater than the density of the ISA atmosphere at FL 180.
    • DLess than the density of the ISA atmosphere at FL 180
    Show answer

    Correct answer: C. Greater than the density of the ISA atmosphere at FL 180.

    This Explanation is Coming Soon

  8. Q8

    Under what condition does pressure altitude have the same value as density altitude?

    • AAt sea level when the temperature is 0°C.
    • BWhen the altimeter has no position error.
    • CWhen the altimeter setting is 1013,2 hPa.
    • DAt standard temperature.
    Show answer

    Correct answer: D. At standard temperature.

    This Explanation is Coming Soon

  9. Q9

    Density is _____ at poles than equator

    • AHigher
    • BLower
    • CSame
    Show answer

    Correct answer: A. Higher

    Polar air is cold and therefore dense, so at the surface density is higher at the poles than at the warm equator, where the heated, expanded air is comparatively light.

  10. Q10

    Above 8 km density is ______ at poles than at equator

    • AHigher
    • BLower
    • Csame
    Show answer

    Correct answer: B. Lower

    In the cold polar air column pressure falls off with height much more rapidly than in the warm equatorial column, so above about 8 km the pressure, and with it the density, is lower over the poles than over the equator. The surface relationship is thus reversed at altitude.

  11. Q11

    The altitude in ISA at which air density is the same as the observed density is

    • ADensity Altitude
    • BISA Density
    • CReal Density
    Show answer

    Correct answer: A. Density Altitude

    Density altitude is defined as the altitude in the International Standard Atmosphere at which the prevailing (observed) air density occurs; it is the single figure that summarises the effect of pressure, temperature and humidity on aircraft performance.

  12. Q12

    Density is usually expressed as

    • AKg/sq n
    • Bg/cu m
    • CN/sq m
    Show answer

    Correct answer: B. g/cu m

    Air density is customarily expressed in grams per cubic metre, mass per unit volume; at mean sea level in ISA it is about 1225 g per cubic metre.

9 more Air Density questions in the full bank

Create a free account to practise every Air Density question with instant scoring, chapter tests, previous DGCA papers and full-length mock exams.

Start practising free

More DGCA Meteorology topics