Our Earth is ALWAYS spinning. Yet, j[i]ust how fast[/i] is earth rotating? [br][br]Everyone on Earth spins 360 degrees in a 24 hour period. 360 degrees / 24 hrs = 15 degrees per hour. [br]This is Earth's ANGULAR SPEED ([i]amount of rotation[/i] per [i]unit time[/i]). This remains constant. [br][br]Yet what's [b]NOT CONSTANT[/b] is one's [b]LINEAR SPEED[/b] ([i]distance traveled[/i] per [i]unit time[/i]). [br]In a 24 hour period, we all--(unless we're flying a great distance in an airplane)--"spin along" a circle of latitude. [br]Some circles of latitude are bigger than others. (Observe in the applet below.) [br]Since this is the case, we [b]CANNOT ALL HAVE the same LINEAR SPEED[/b] as every other person on the planet! [br][br][color=#1551b5][b]Let's assume Earth to be a perfect sphere [/b][/color]([i]for simplicity's sake![/i]) [br]According to NASA's website (http://solarsystem.nasa.gov/planets/profile.cfm?Display=Facts&Object=Earth), [br]Earth has a [color=#d69210][b]mean radius of 3,958.8 miles.[/b][/color] [br]To successfully answer the 2 questions in this applet, all you will need is the following: [br][br]1) [color=#b20ea8]The latitude of your location [/color][br]2) A good working knowledge of some basic geometry formulas. [br]3) A good working knowledge of basic right-triangle trigonometry. [br][br]Have fun with this! [b]([i]Don't check a checkbox before answering the question that precedes it![/i])[/b]