The speed of sound is the speed at which sound waves propagate through a medium, such as air or water. In dry air at a temperature of around 20 degrees Celsius (68 degrees Fahrenheit), the speed of sound is approximately 343 meters per second, or about 1,235 kilometers per hour (767 miles per hour).
Reaching or exceeding the speed of sound is referred to as supersonic speed. While it is possible for certain vehicles to achieve supersonic speeds, it depends on the specific design and capabilities of the vehicle.
Cars: Supersonic speeds are not achievable with conventional cars. The fastest land vehicles, such as land speed record cars, have not exceeded the speed of sound. The speed of sound poses significant engineering challenges and safety concerns for terrestrial transportation.
Planes: Supersonic speeds have been achieved by certain aircraft. The famous Concorde passenger airliner, for example, was capable of flying faster than the speed of sound. However, the Concorde was retired in 2003, and currently, there are no commercial passenger aircraft flying at supersonic speeds. There are ongoing efforts to develop new supersonic commercial aircraft, but they are still in the testing and development stages.
Spacecraft: In the context of space travel, spacecraft can reach speeds far greater than the speed of sound. When a spacecraft leaves the Earth's atmosphere, it enters the realm of orbital or interplanetary travel. Orbital velocities, for instance, are typically several kilometers per second, which is much higher than the speed of sound. Spacecraft traveling to other celestial bodies, such as the Moon or Mars, also achieve velocities far beyond the speed of sound.
It's worth noting that the concept of speed of sound and supersonic speeds is specific to the medium through which sound propagates, like air or water. In the vacuum of space, there is no sound because there is no medium for sound waves to travel through, so the notion of the speed of sound is not applicable.