Less than the speed of sound in that medium.
If accelerating to the speed of sound, the subsonic.
Subsonic means "slower than the speed of sound" so a subsonic bullet is any bullet that travels slower than the speed of sound.
Transonic being past the speed of sound and subsonic is below the speed of sound.
subsonic is moving below the speed of sound, supersonic is faster than speed of sound
Subsonic is below or slower than the speed of sound, and supersonic is above or faster than the speed of sound.
Subsonic means any speed below the speed of sound. (Mach 1). So subsonic aircraft range from 0 - 661 knots at sea level. (Mach 1 is 661 knots at sea level.)
Subsonic
subsonic
One half the speed of sound. This is subsonic.
Speed has nothing to do with where you are. You can travel below the speed of sound pretty much anywhere.
The term subsonic can refer to speed that's lower than the speed of sound. In computer terms, this could mean an open source media server or refer to programming code.
A subsonic aircraft doesn't produce a sonic boom because it is subsonic, and cannot produce enough speed to do so. A sonic boom is created when an aircraft becomes supersonic, accelerating past the speed of sound. Since it is traveling near the speed of sound at this time, the sound waves build up around it, finally traveling through the air as it is left behind by the aircraft.