Tuesday, April 06, 2010

Treadmills, aces, U.S. States and the earth's rotation

- When you run on a treadmill, you try to keep your speed the same as the treadmill, so you don't slip off the treadmill or move too far ahead on the treadmill.  What if an airplane on the ground did the same thing on a treadmill? Could the airplane get off the ground?

- While playing a game of cards, during the first hand you announce to everyone that you have an ace.  Later in the night, during another hand of cards and playing the same card game, you announce that you have the ace of spades.  For which hand did you have a greater chance of getting a second ace?  It seems like they would be equal, but they are not:

- U.S. States that might have been:

- I watched a TV show on National Geographic last night about what would happen if the earth stopped rotating after a few years.  The bottom line: you're dead.  Yes, even you.  Fascinating stuff.  You don't realize how much of our survival depends on the earth rotating at roughly 1,000 MPH.  The earth is very slowly losing its rotation. The earth wont completely lose it's rotation for another 28 billion years.  The earth is due to be swallowed by our Sun, which turns into a red giant in about a billion years, so I wouldn't get too worked up about it:

- Facebook figures for the United States:


Randal said...

Jesus Christ, do you have any idea what that airplane on a treadmill question did to the Dope? Blood was spilled. It's still one of the Topics That May Not Be Discussed there. I can't believe you linked to that can of worms...

Greymarch said...

It's caused that much trouble at The Dope, huh? My intuition says that the plane couldn't fly because it's not generating lift under its wings, due to lack of forward movement. However, all the articles I have read about the conundrum state that the plane would lift-off and fly.

Randal said...

Oh my yes. I quit posting there about a year ago, after I almost got banned lighting into the 95% liberal user-base there, but I still read some of the less charged forums, and that topic...and it comes up about once a year...makes people go ape-shit. The Mythbusters crew actually did an episode on it:


because of the controversy that was brought up by the question on the Straight Dope!

Sterance said...

The reason most people are convinced the plane could not take off is because they fail to realize that a plain's wheels are free spinning with no drag one way, and no thrust the other (sure there is friction, but not nearly enough to dwarf the thrust put forth but a turbo jet engine).

Once you realize the wheels affect nothing, its clear to see that even without experimentation, the plane's engine thrust would push it forward as usual (and the wheels would actually be spinning twice as fast to no great affect).

The people that propagated this myth probably could not consider the fact that a plane's wheels are only used for resting the plane on, no propulsion.