| 释义 |
standard atmospheric conditions standard atmospheric conditionsThe internationally accepted conditions of the atmosphere to allow all measurements to be brought to the same norms. The standard atmospheric conditions at sea level are pressure: 29.92 in of mercury or 1013.2 hectopascals; temperature: 15°C; acceleration due to gravity: 32.174 ft/s2 or 9.809 m/s2; air density: 0.002378 slugs/ft3 or 1.225 kg/m3; and speed of sound: 761 miles/h, 1116.4 ft/s, 1225.35 km/h, or 34,046.16 cm/s. The temperature lapse rate is assumed to be constant at the rate of 1.98°C per 1000 ft (6.5°C per kilometer) up to a height of 36,090 ft (11 km), above which it remains constant at -56.5°C. See ICAN Atmosphere. |