Final answer:
The exact density altitude for the provided conditions requires standard atmospheric tables or a flight computer for calculations. Density altitude is affected by pressure, temperature, and altitude, with air density decreasing as altitude increases. Without specific charts or calculators, the precise density altitude cannot be provided in this response.
Step-by-step explanation:
The density altitude for the given conditions of an altimeter setting at 29.25'' Hg, runway temperature of +81F, and airport elevation at 5250ft MSL can be calculated using standard atmospheric tables and correction factors. First, convert the given altimeter setting to the equivalent sea level pressure and then use the temperature to find the pressure altitude. After that, apply temperature deviations from the standard atmosphere to correct the pressure altitude to density altitude. However, without the use of a flight computer or a specific density altitude chart for the given conditions, we cannot provide an exact number here, as the standard atmospheric tables or correction charts are required to perform the necessary calculations. Pilots often use density altitude charts or electronic flight computers to accurately determine this value, taking into account the specific conditions at the airport.
To understand the concept further, we can use the provided information regarding air density and how it changes with altitude. For example, the air density decreases with increasing altitude, which can be observed through the relationship demonstrated by the slope calculation between points representing altitudes of 4,000 meters and 6,000 meters.