Convert Foot/Second (ft/s) to Cosmic Velocity - First (v₁) instantly.
About these units
Foot/Second (ft/s)
The foot per second is an imperial speed unit used in engineering, ballistics, aviation, and certain sports sciences. It expresses the number of feet traveled per second. Ballistics experts use ft/s to measure bullet velocities and projectile speeds, particularly in countries with strong imperial-unit traditions. Engineers may use ft/s in fluid flow calculations or mechanical system design when working with legacy data. Although ft/s is rarely seen in daily life, it remains relevant in niche disciplines where imperial units dominate, offering a smaller, more precise scale than mph.
Cosmic Velocity - First (v₁)
The first cosmic velocity is the minimum horizontal speed an object must achieve to enter a stable orbit around a planetary body without additional propulsion. For Earth, this value is about 7.9 km/s. At this speed, an object's forward motion precisely balances with the gravitational pull downward, creating continuous free-fall—the essence of orbital motion. This velocity is foundational in orbital mechanics. Spacecraft reaching Low Earth Orbit (LEO) must achieve at least this horizontal speed, even if their vertical ascent profile varies. Understanding v₁ was essential in the early space age: it represented the threshold between atmospheric flight and true spaceflight, marking human entry into the orbital era.