The formula for Coriolis acceleration:

a = F / m = 2 * v * ω * sin(α)

F is the Coriolis force,
m is the mass of the moving object,
v is the velocity of the moving object,
ω is the angular velocity of the Earth, ω = 2π/24h ≈ 0.0000727 1/s
α is the latitude at which the object is located.

Note that Coriolis force/acceleration is directly proportional to the velocity of the object in relation to the surface of the earth. If something is not moving in relation to the surface of the earth such as a hovering helicopter, Coriolis force/acceleration is Zero. If something is moving very slowly, such as a hot air balloon, Coriolis force/acceleration is very small.

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