Calculadora de Velocidade Terminal
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
v_t = √(2mg/(ρ·Cd·A))
About this calculator
The terminal velocity calculator determines the maximum speed a falling object reaches when air drag balances its weight. At this point, acceleration stops and the object falls at constant speed. The formula used is v_t = √(2mg/(ρ·Cd·A)), where m is mass, g gravity, ρ fluid density, Cd drag coefficient, and A frontal area. The calculator allows varying all these parameters.
To use, enter values such as object mass, air density (default 1.225 kg/m³ at sea level), frontal area, and drag coefficient (e.g., 0.47 for a sphere, 0.82 for a parachute). The result is terminal velocity in m/s or km/h. This tool is useful for understanding phenomena like raindrop fall, skydiving, or vehicle design.
Use cases include safety analysis in free-fall sports, parachute sizing, study of sedimentation in fluids, or comparison of objects with different shapes and masses. For example, a typical raindrop reaches about 9 m/s, while a skydiver with an open parachute has a terminal velocity of about 5-6 m/s.
Cautions: the model assumes turbulent drag (high Reynolds regime) and neglects buoyancy. For very small objects or low speeds, viscous drag (Stokes) is more appropriate. Also, air density varies with altitude, and the drag coefficient depends on object orientation. Use realistic values to obtain approximate real-world results.
Frequently asked questions
What is the terminal velocity of a skydiver in free fall?
A skydiver in free fall reaches about 53 m/s (190 km/h) in belly-down position, but can reach 90 m/s (320 km/h) in a vertical dive.
Does the calculator work for objects falling in water?
Yes, just adjust the fluid density (water: 1000 kg/m³) and drag coefficient. However, for submerged objects, consider buoyancy, which is not included.
How do I obtain the drag coefficient of an object?
Typical values: sphere 0.47, cylinder 0.82, flat plate 1.28, car 0.3-0.5. For accuracy, consult tables or perform computational simulations.
Does terminal velocity depend on drop height?
No, terminal velocity is the limiting speed independent of height, provided there is enough space to reach it. The height needed to reach 99% of terminal is about 10 times the adjustment distance.
What happens if air density is very low?
With lower density (high altitude), drag decreases and terminal velocity increases. For example, at 10 km altitude, density is ~0.4 kg/m³, resulting in higher terminal velocities.