In dry air (68F) the speed of sound is 343 meters per second
Chat with our AI personalities
The speed of sound varies greatly, depending on the material it goes through - in some cases, by a factor of 5 or more. The speed of sound in air will depend slightly on temperature, pressure, etc., but it is about 340 meters/second. I'll leave it up to you to convert that to mph.
Velocity is a vector quantity that measures speed (and also includes direction). 55 mph is a speed. 55mph North is a velocity.
mph is a measure of speed, km is a measure of distance. Speed = Distance/Time. You cannot convert distance into speed without knowledge of the time taken for the journey.
The speed of sound is around 760 miles per hour = Mach 1. So Mach 4 is 4*760 = 3040 mph.
Average speed is 50 mph [(40+60)/2].