Haha. When I used to instruct I would say, "Good question Bloggs, research it and tell me all about it all when you're next in."
They never forgot..!
V^2 / [ R cos(Lat) ] where:
Lat is the latitude, v is the surface's rotational speed at that latitude, and R is the earth's radius.
If the rotational speed 'v' is increased by a wind speed 'u', the difference is:
(v+u)^2 - v^2 = 2vu + u^2 (but u^2 is small enough to ignore).
So the increase in CF is: 2vu / [ R cos(Lat) ]
but v / [ R cos(Lat) ] is Rot, the Earth's rate of rotation,
so we have: 2 u Rot
Finally, noting that the component along the earth's surface is sin(Lat)
we get the full Coriolis Effect: 2 u Rot sin(Lat).
An excellent explanation - almost all my students had this equation easily to hand on short finals
