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Therefore, for a boom to reach the ground, the aircraft's speed relative to the ground must be greater than the speed of sound at the ground. For example, the speed of sound at 30,000 feet (9,100 m) is about 670 miles per hour (1,080 km/h), but an aircraft must travel at least 750 miles per hour (1,210 km/h) (Mach 1.12) for a boom to be heard ...
The Enhanced Fujita scale replaced the decommissioned Fujita scale that was introduced in 1971 by Ted Fujita. [6] Operational use began in the United States on February 1, 2007, followed by Canada on April 1, 2013, who uses a modified version known as the CEF-scale.
Supersonic speed is the speed of an object that exceeds the speed of sound (Mach 1). For objects traveling in dry air of a temperature of 20 °C (68 °F) at sea level , this speed is approximately 343.2 m/s (1,126 ft/s; 768 mph; 667.1 kn; 1,236 km/h).
This was solved in later models with changes to the wing. Worse still, a particularly dangerous interaction of the airflow between the wings and tail surfaces of diving Lockheed P-38 Lightnings made "pulling out" of dives difficult; in one 1941 test flight test pilot Ralph Virde was killed when the plane flew into the ground at high speed. [8]
The most noticeable aspect of lightning and thunder is that the lightning is seen before the thunder is heard. This is a consequence of the speed of light being much greater than the speed of sound. The speed of sound in dry air is approximately 343 m/s (1,130 ft/s) or 1,236 km/h (768 mph) at 20 °C (68 °F; 293 K). [19]
A new featurette on the making of the Paramount action tentpole reveals Cruise learned how to speed-fly, which director Christopher McQuarrie calls “one of the most dangerous […]
To quantify just how much more dangerous American roads are over the New Year's holiday, Sargon Law Group analyzed records of more than 12,000 fatal car crashes from the National Highway Transit ...
Whenever the vehicle changes either direction or speed, the occupants feel lateral (side to side) or longitudinal (forward and backwards) forces produced by the mechanical push of their seats. The expression "1 g = 9.806 65 m/s 2 " means that for every second that elapses, velocity changes 9.806 65 metres per second ( 35.303 94 km/h ).