Yard per Second to Millimeter per Second

Yard per second measures distance in yards traveled in one second.

1 yd/s = 0.9144 m/s = 3.29 km/h = 2.045 mph = 3 ft/s.

To ft/s: × 3. To m/s: × 0.9144. To mph: × 2.045.

Sprint speeds in track and field (10–12 yd/s for elite sprinters), projectile velocities, and some fluid flow measurements.

Usain Bolt peak: ~13.5 yd/s. NFL wide receiver sprint: ~11 yd/s. Baseball thrown: ~40–45 yd/s.

Confusing with ft/s — yd/s is 3× faster. Mixing up with mph.

1 yd/s = 3 ft/s = 0.9144 m/s. Multiply by ~2 to get approximate mph.

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.