How this calculator works
This local horizontal model uses the vertical component of planetary rotation. It gives a sideways acceleration perpendicular to horizontal motion: right in the northern hemisphere and left in the southern hemisphere for prograde rotation. Latitude is entered as a magnitude plus a hemisphere. Vertical motion and the vertical Coriolis component are outside this approximation.
Formula
a_horizontal = 2 Omega v sin(latitude); F = m a_horizontal. The full vector relation is a_C = -2 Omega cross v.
Worked example
At a pole, Omega = 0.01 rad/s and speed 10 m/s give 0.2 m/s². A 2 kg object then has a 0.4 N sideways force. At the equator this horizontal component is zero.
Advertisement
Frequently asked questions
Is the Coriolis effect zero at the equator?
The horizontal component for horizontal motion is zero. Other components of the full vector effect can remain.
Does the force change speed?
The Coriolis force is perpendicular to velocity in the rotating frame, so it does no work.
Why is hemisphere a separate choice?
It controls the direction while latitude magnitude controls the size of the horizontal effect.