Mach (20°C, 1 atm) to Millimeter 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.

Millimeter per minute measures small distances in millimeters traveled over one minute.

1 mm/min = 0.001 m/min = 0.0000167 m/s = 0.00006 km/h.

To m/s: ÷ 60,000. To cm/min: ÷ 10. To m/min: ÷ 1,000.

CNC machine feed rates (50–500 mm/min for cutting), 3D printer speeds, medical infusion pumps, and slow actuator movements.

3D printer typical: 40–150 mm/min. Slow drill feed: 10–100 mm/min. Medical IV drip: 1–50 mm/min (linear displacement).

Confusing with mm/s (60× faster) or cm/min (10× faster).

1,000 mm/min = 1 m/min. Very common in machining. Good for precision movements.