Current is measured in Amperes (usually just referred to as âAmpsâ). An ampere is defined as 6.241*10 18 electrons (1 Coulomb) per second passing through a point in a circuit. Amps are represented in equations by the letter âIâ.
The X-1, piloted by Chuck Yeager, was the first manned airplane to exceed the speed of sound in level flight and was the first of the X-planes, a series of American experimental rocket planes (and non-rocket planes) designated for testing of new technologies and often kept secret.
Currently, the X-15 still holds the official world record for the fastest speed ever reached by a manned aircraft: Mach 6.72, which is 6.72 times the speed of sound, or 4,520 mph (7,274 km/h).