Mach (20°C, 1 atm) to Mile per Minute

Mach number is the ratio of an object's speed to the speed of sound in the surrounding medium. Mach 1 at 20°C, 1 atm equals approximately 343.6 m/s (1,235 km/h).

Mach = velocity ÷ speed_of_sound. At 20°C: Mach 1 = 343.6 m/s. Speed of sound = √(γRT/M) where γ = heat capacity ratio.

To m/s (at 20°C): × 343.6. To km/h (at 20°C): × 1,237. Note: changes with altitude and temperature.

Fighter jets (Mach 1.5–2.5), commercial aircraft (Mach 0.8–0.85), space shuttle reentry (Mach 25), and missile speeds.

Concorde: Mach 2.04. SR-71 Blackbird: Mach 3.3. X-15: Mach 6.7. Meteorites enter at Mach 50+. Subsonic <1, supersonic >1, hypersonic >5.

Thinking Mach is constant — it varies with temperature/altitude. At 30,000 ft, Mach 1 ≈ 295 m/s (colder air = slower sound).

Mach 1 = speed of sound. Below Mach 1 = subsonic. Mach 1–5 = supersonic. Above Mach 5 = hypersonic. It's a ratio, not a fixed speed.

Mile per minute measures the number of statute miles traveled in one minute. Used for very high speeds in imperial units.

1 mi/min = 60 mph = 96.56 km/h = 26.82 m/s.

To mph: × 60. To km/h: × 96.56. To m/s: × 26.82.

Aircraft speeds (commercial jets: 8–10 mi/min), high-speed trains, missile velocities, and meteor observations.

Commercial jet cruise: ~9 mi/min (540 mph). Military jet: 15–25 mi/min. Space shuttle reentry: ~300 mi/min.

Confusing with mph — 1 mi/min is 60 times faster than 1 mph.

Simple conversion: mi/min × 60 = mph. Example: 10 mi/min = 600 mph. Good for aviation mental math.