Cosmic Velocity - Second to Centimeter per Second

The second cosmic velocity (Earth's escape velocity) is approximately 11,200 m/s (11.2 km/s), the minimum speed to escape Earth's gravity completely.

v₂ = √(2GM/r) = √2 × v₁ ≈ 11.2 km/s. Exactly √2 times the first cosmic velocity.

To km/h: × 3,600. To mph: × 25,000. 11.2 km/s = 40,320 km/h = 25,053 mph.

Moon missions, Mars missions, deep space probes (Voyager, New Horizons), and any mission leaving Earth's gravity well.

Apollo missions: ~11.2 km/s. Voyager probes: exceeded v₂ to leave solar system. New Horizons: launched at record 16.26 km/s (fastest ever from Earth).

Thinking you need this speed everywhere — you only need it at launch. In space, much less Δv is needed.

~11 km/s to escape Earth. √2 × orbital velocity. Remember: orbit ≈ 8 km/s, escape ≈ 11 km/s.

Centimeter per second measures distance in centimeters traveled in one second. Common for small-scale movements and flows.

1 cm/s = 0.01 m/s = 0.036 km/h = 0.6 m/min.

To m/s: ÷ 100. To km/h: × 0.036. To mm/s: × 10.

Stream/river surface flow (10–200 cm/s), blood flow velocity in arteries (10–100 cm/s), small machine movements, and insect flight speeds.

Housefly speed: ~200 cm/s. Blood in aorta: ~40 cm/s. Small stream flow: 30–100 cm/s. Ant running: 1–3 cm/s.

Confusing cm/s with m/s — off by a factor of 100. Mixing up with mm/s.

100 cm/s = 1 m/s. Good for water flow, blood flow, and small animal speeds. Divide by 100 to get m/s.