Mach (20°C, 1 atm) to Meter per Second

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.

The meter per second is the SI derived unit of speed and velocity, defined as the distance traveled in meters over time in seconds. It represents how many meters an object moves in one second.

1 m/s = base unit. Direct relationship with distance (m) and time (s). Speed = distance ÷ time.

To km/h: × 3.6. To mph: × 2.237. To ft/s: × 3.281. To knots: × 1.944.

Walking speed (1.4 m/s average), running speed (elite sprinters reach 12.4 m/s), vehicle speeds in scientific contexts, and wind speed measurements.

Usain Bolt's top speed: 12.4 m/s (44.6 km/h). Cheetah speed: 29 m/s. Speed of sound at sea level: 343 m/s. Light: 299,792,458 m/s.

Confusing m/s with km/h — a common error when reading speedometers. Remember: multiply m/s by 3.6 to get km/h.

Quick conversion: 10 m/s ≈ 36 km/h. To visualize: 1 m/s means moving one big step per second. Multiply by 3.6 for km/h.