Calculator Inputs
Example Data Table
| Scenario | Mode | Mass | Speed | Rotation Input | Angle / Latitude | Acceleration | Force |
|---|---|---|---|---|---|---|---|
| Lab turntable test body | General | 5 kg | 12 m/s | 0.8 rad/s | 60° | 16.63 m/s² | 83.14 N |
| High-speed aircraft at 45° latitude | Planetary | 80 kg | 250 m/s | Earth rate | 45° | 0.0258 m/s² | 2.07 N |
| Vehicle on equatorial route | Planetary | 1200 kg | 30 m/s | Earth rate | 0° | 0 m/s² | 0 N |
Formula Used
General rotating frame: Coriolis force magnitude is F = 2mωv sin(θ). The related Coriolis acceleration is a = 2ωv sin(θ).
Planetary surface approximation: The Coriolis parameter is f = 2Ω sin(λ). For horizontal motion, magnitude becomes a = |f|v = 2Ωv|sin(λ)|, and force is F = ma.
Symbols: m is mass, ω or Ω is angular speed, v is speed relative to the rotating frame, θ is angle with the rotation axis, and λ is latitude.
How to Use This Calculator
- Choose General rotating frame for a turntable, rotor, or custom rotating system.
- Choose Planetary surface approximation for Earth-like latitude-based motion.
- Enter the object mass, motion speed, and your preferred input units.
- For general mode, enter angular speed and the angle between motion and the rotation axis.
- For planetary mode, enter latitude, planetary rotation rate, and travel direction.
- Press Calculate Coriolis Force to view the result above the form, then export it as CSV or PDF.
FAQs
1. What does the Coriolis force represent?
It is an apparent force observed in a rotating reference frame. It changes motion direction relative to that frame and depends on mass, rotation rate, speed, and geometric orientation.
2. Why is the result zero at the equator?
In the horizontal latitude model, the Coriolis parameter is proportional to sin(λ). At zero latitude, that sine term is zero, so the horizontal Coriolis magnitude becomes zero.
3. Why is angle needed in general mode?
Only the velocity component perpendicular to the rotation vector contributes. The sine term captures that geometry, so 90° gives the largest effect and 0° gives none.
4. Why does the deflection side change by hemisphere?
The sign of the latitude term changes across the equator. That reverses the sideways acceleration direction, producing rightward deflection in the north and leftward deflection in the south.
5. Can I use this for projectiles or long-range paths?
Yes, for first-pass estimates. Very long flights, ballistic paths, and full trajectory work usually need full vector equations, gravity, drag, curvature, and time integration.
6. Which units can this calculator handle?
It accepts kilograms, grams, pounds, several speed units, and angular velocity in radians per second, rpm, or degrees per second. All values are converted internally.
7. Why are daily Coriolis forces often small?
Earth rotates slowly in angular terms, so the resulting acceleration is usually modest for everyday speeds. The effect grows with speed, latitude, and travel distance.
8. What does the travel direction option change?
It does not change the force magnitude in the latitude model. It only helps describe the sideways deflection direction relative to the selected heading.