Horizontal sundial calculations: Difference between revisions

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{{task|sciences}}[[Category:Mathematics]]
{{task|sciences}}
[[Category:Mathematics]]

;Task:
Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an ''operator'' entered location.
Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an ''operator'' entered location.



For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of [[wp:Jules Verne|Jules Verne]]'s ''[[wp:The Mysterious Island|Lincoln Island]]'', aka ''[[wp:Ernest Legouve Reef|Ernest Legouve Reef]])'', with a legal meridian of 150°W.
For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of [[wp:Jules Verne|Jules Verne]]'s ''[[wp:The Mysterious Island|Lincoln Island]]'', aka ''[[wp:Ernest Legouve Reef|Ernest Legouve Reef]])'', with a legal meridian of 150°W.
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Wikipedia: A [[wp:sundial|sundial]] is a device that measures time by the position of the [[wp:Sun|Sun]]. In common designs such as the horizontal sundial, the sun casts a [[wp:shadow|shadow]] from its ''style'' (also called its [[wp:Gnomon|Gnomon]], a thin rod or a sharp, straight edge)<!-- The style is the time telling edge of the gnomon, Waugh,1973 p29--> onto a flat surface marked with lines indicating the hours of the day (also called the [[wp:Sundial#Terminology|dial face]] or dial plate). As the sun moves across the sky, the shadow-edge progressively aligns with different hour-lines on the plate. Such designs rely on the style being aligned with the axis of the Earth's rotation. Hence, if such a sundial is to tell the correct time, the style must point towards [[wp:true north|true north]] (not the [[wp:North Magnetic Pole|north]] or [[wp:Magnetic South Pole|south magnetic pole]]) and the style's angle with horizontal must equal the sundial's geographical [[wp:latitude|latitude]].
Wikipedia: A [[wp:sundial|sundial]] is a device that measures time by the position of the [[wp:Sun|Sun]]. In common designs such as the horizontal sundial, the sun casts a [[wp:shadow|shadow]] from its ''style'' (also called its [[wp:Gnomon|Gnomon]], a thin rod or a sharp, straight edge)<!-- The style is the time telling edge of the gnomon, Waugh,1973 p29--> onto a flat surface marked with lines indicating the hours of the day (also called the [[wp:Sundial#Terminology|dial face]] or dial plate). As the sun moves across the sky, the shadow-edge progressively aligns with different hour-lines on the plate. Such designs rely on the style being aligned with the axis of the Earth's rotation. Hence, if such a sundial is to tell the correct time, the style must point towards [[wp:true north|true north]] (not the [[wp:North Magnetic Pole|north]] or [[wp:Magnetic South Pole|south magnetic pole]]) and the style's angle with horizontal must equal the sundial's geographical [[wp:latitude|latitude]].
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=={{header|Ada}}==
=={{header|Ada}}==