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Small-Scale Question Sunday for March 17, 2024

Do you have a dumb question that you're kind of embarrassed to ask in the main thread? Is there something you're just not sure about?

This is your opportunity to ask questions. No question too simple or too silly.

Culture war topics are accepted, and proposals for a better intro post are appreciated.

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I'm trying to calculate the strength of solar radiation for a given latitude as a simple factor from 1 (equatorial) to 0 (polar), assuming no axial tilt or any other complications. My trigonometry is weak. How do I do this?

Arccos curve looks good. Is it arccos? Arccos(latitude / 90) * (2 / pi) looks pretty decent.

Edit: It was Cos all along!

arccos is gonna give you too sharp a result near the equator (i.e. predict that the last few degrees as you get closer matter the most). What you want is just cos(latitude/90 * pi/2).

edit: the way you visualise this is by holding a square piece of paper in front of you, and tilting it until you're looking at it edge-wise. The "visual area" of the piece of paper in your field-of-view is what will give you the proportionality factor.

Yep, that does the trick. Thanks!