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.
Chuck Yeager and the X-1 research plane that broke the sound barrier in 1947. It can be seen today at the Smithsonian Air & Space Museum in Washington, D.C. The speed of sound varies depending on the temperature of the air through which the sound moves. On Earth, the speed of sound at sea level â assuming an air temperature of 59 degrees Fahrenheit (15 degrees Celsius) â is 761.2 mph (1,225 km/h). Because gas molecules move more slowly at colder temperatures, that slows the speed of sound; sound moves faster through warmer air.