Talk:1318: Actually

Explain xkcd: It's 'cause you're dumb.
Revision as of 08:58, 17 January 2014 by 108.162.229.65 (talk) (Centripetal vs Centrifugal force)
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I started reading the comic from the topmost line "Actually, measurements suggest it's flat." It seemed that he was talking about the planet, but it's also a response to the curved-space line from before. Upon further reading, I can't tell if the discussion is about a planet or a universe, and it looks like you can go around the circle twice and assume both. 173.245.50.72 05:13, 17 January 2014 (UTC)

It is about the shape of the Earth. The Earth exists in a curved universe. The alt text is referring to the fact that by being more and more specific you can always get the last word in but it may alienate you from your peers. 108.162.246.117 05:14, 17 January 2014 (UTC)

The transcript needs some way to show that Cueball is talking to the second Hairy in the end. 108.162.216.71 08:25, 17 January 2014 (UTC)

"show that Cueball is talking to the second Hairy in the end" -> Do you consider it done ? MGitsfullofsheep (talk) 08:50, 17 January 2014 (UTC)

Fixed factual error about sum of angles of a triangle in a closed geometry. An example of closed geometry is spherical geometry, where sum of angles of a triangle is π < A + B + C<3π http://en.wikipedia.org/wiki/Spherical_trigonometry . Previous text wrongly stated that A+B+C would be smaller than π in closed geometry and greater in open geometry. MGitsfullofsheep (talk) 08:50, 17 January 2014 (UTC)

About the oblate configuration: why attribute it to centripetal force? Because centrifugal force is an "apparent" force? Well centripetal force from gravitational pull is actually balancing the centrifugal force caused by rotation of the earth. The whole "centrifugal force does not exist" thing is a misconception. It's an inertial force and writing the equilibrium equations for an object in the rotating reference frame (the one we experience everyday) at latitude phi you see: gravitational pull toward the center of the planet + centrifugal force away from the axis of rotation= mass*g(phi). This g(phi) is not the same in every spot of the earth, it changes in value and direction (does not always point exactly to the center of the earth) with latitude.