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.
Corcord could go much faster, mach 2. Some military planes much faster still, mach 5. Mach is speed of sound but is not a fixed value. Speed of sound varies with air pressuure. At 35,000 feet (a typical cruising altitude for long haul), mach 1 is about 663mph. Faster planes have to fly higher for lower air resistance & better fuel economy.