On a RADAR screen an operator spots some kind of aircraft, flying 1200 feet per second at an altitude of 14 kilometres. What flight regime is this aircraft in?
Subsonic, Transonic, supersonic, Hypersonic
To determine the flight regime of the aircraft, we need to compare the aircraft's speed to the speed of sound.
The speed of sound is approximately 1125 feet per second (at sea level and 20 degrees Celsius).
Since the aircraft is flying at 1200 feet per second, which is greater than the speed of sound, it is flying at a supersonic speed.
To determine the flight regime of the aircraft, we need to compare its speed to the speed of sound. The speed of sound can vary depending on various factors such as temperature and altitude, but for simplicity, we will use the commonly accepted value of approximately 1,125 feet per second (343 meters per second) at sea level and 20 degrees Celsius.
Given that the aircraft is flying at 1200 feet per second, which is greater than the speed of sound, we can conclude that the aircraft is in the supersonic flight regime.
Keep in mind that this calculation assumes that the aircraft is flying at sea level and the temperature is around 20 degrees Celsius. If these conditions differ significantly, the speed of sound will also vary, and the flight regime determination could change accordingly.
To determine the flight regime of the aircraft, we need to compare its speed to the speed of sound at that altitude.
At sea level, the speed of sound is approximately 1,125 feet per second. However, at higher altitudes, where this aircraft is flying, the speed of sound decreases.
To find the speed of sound at an altitude of 14 kilometers (which is approximately 45,931 feet), we can use the equation:
Speed of sound (feet per second) = 1,125 feet per second * √(altitude in feet/ sea level altitude in feet)
Speed of sound = 1,125 feet per second * √(45,931 feet/ 0 feet)
Speed of sound ≈ 1,125 feet per second * √(45,931)
Speed of sound ≈ 1,125 feet per second * 214.19
Speed of sound ≈ 240,976 feet per second
Now, we can compare the speed of the aircraft (1200 feet per second) with the speed of sound (240,976 feet per second) at that altitude.
Since the aircraft's speed (1200 feet per second) is less than the speed of sound (240,976 feet per second), we can conclude that the aircraft is in the subsonic flight regime.