# How Fast are You Spinning?

- Author:
- Tim Brzezinski

Our Earth is ALWAYS spinning. Yet, j

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