Millimeter per Second to Knot (UK)

Millimeter per second measures distance in millimeters traveled in one second. Used for small-scale movements and precise measurements.

1 mm/s = 0.001 m/s = 0.0036 km/h = 0.06 m/min.

To m/s: ÷ 1,000. To cm/s: ÷ 10. To km/h: × 0.0036.

Vibration measurements (machinery typically 0.1–50 mm/s RMS), small motor speeds, precision linear actuators, and tape/film transport speeds.

Machinery vibration: >10 mm/s indicates problems. Seismic activity: 0.001–100 mm/s. CD/DVD read head: 1.2–1.4 mm/s linear velocity.

Confusing mm/s with cm/s (10× different) or m/s (1000× different).

1,000 mm/s = 1 m/s. Very common in vibration analysis. 10 mm/s RMS is a typical machinery vibration threshold.

The UK knot is a historical variation of the knot based on the British nautical mile (6,080 feet) rather than the international nautical mile (6,076.12 feet).

1 UK knot ≈ 1.853184 km/h = 0.5148 m/s. Slightly faster than the international knot (1.852 km/h).

To international knots: × 1.00064. To km/h: × 1.853. To m/s: × 0.5148.

None in modern use. Only relevant for interpreting historical British naval records.

The difference between UK and international knots is only 0.064% — barely noticeable but important for precise navigation.

Assuming all old British ship logs use the same knot as today — they don't, but the difference is tiny.

Historical only. Effectively identical to modern knot. Only matters for historical maritime research.