Velocidade Stokes
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
About this calculator
The Stokes Velocity Calculator is an online tool that allows users to calculate the terminal velocity of a particle in a fluid, considering the physical properties of the system. The formula used is based on Stokes' Law, which describes the drag force exerted on a sphere moving in a viscous fluid. The terminal velocity is reached when the drag force equals the force of gravity.
The formula for calculating the terminal velocity is v = 2r²g(ρ_p−ρ_f)/(9μ), where v is the terminal velocity, r is the particle radius, g is the acceleration due to gravity, ρ_p is the particle density, ρ_f is the fluid density, and μ is the dynamic viscosity of the fluid. This equation is essential for understanding the behavior of suspended particles in fluids.
The Stokes Velocity Calculator is useful in various applications, such as chemical engineering, fluid physics, and environmental sciences. For example, one can use the calculator to determine the sedimentation velocity of particles in a river or the rise velocity of air bubbles in a liquid. Additionally, the calculator can be used to explore how different system properties affect the terminal velocity.
When using the Stokes Velocity Calculator, it is crucial to be mindful of the units of the variables and ensure that the input values are realistic and accurate. Furthermore, it is essential to remember that Stokes' Law assumes ideal conditions, such as spherical particles and Newtonian fluids, which may not always be the case in real-world situations.
Frequently asked questions
What is terminal velocity?
Terminal velocity is the maximum velocity reached by a particle in a fluid, when the drag force equals the force of gravity.
What are the units of terminal velocity?
Terminal velocity is typically expressed in units of length per time, such as meters per second (m/s) or centimeters per second (cm/s).
Is Stokes' Law valid for all types of fluids?
No, Stokes' Law assumes that the fluid is Newtonian and that the particles are spherical, which may not always be the case in real-world situations.
How does particle density affect terminal velocity?
Particle density directly affects terminal velocity. Denser particles tend to have a higher terminal velocity.
Is fluid viscosity important for calculating terminal velocity?
Yes, fluid viscosity is crucial for calculating terminal velocity. More viscous fluids tend to reduce the terminal velocity of particles.