Wondering about wild grapes

Sunday, January 29, 2017

R.P.M.

How fast does stuff turn?  Usually that speed is expressed in Revolutions Per Minute or RPM around a fixed axis.  If the axis isn't fixed you would get quite a wobble and if you spin too fast, it could tear itself apart.  Now, how fast is a spot on this spinning sphere traveling?  Well, that depends upon where on the sphere that spot is and how big in diameter the sphere is.  Let's take an example.

Let's say that you are standing at the north axis point of Earth (which, by the way, is not exactly at the north pole).  As you stand there, you spin around with the earth at a speed of one revolution per day but your speed in feet per minute or miles per hour is nil.  Now, let us say that you step off that point and start waking away from it.  The further away you get from the axis point (like the north pole), the faster you start moving.  When you reach the equator, you will be going faster than anywhere else (1037 mph) but you would still be turning at the same RPM.  This is all true if the Earth is a perfect sphere, which it isn't.

OK, got that?  Then tell me, how fast are you really going if you are driving down the road from the northeast to the southwest at 65 mph with a 15 mph cross wind and with one window down in the state of Texas?  Now have a great day, you hear?





14 comments:

  1. Gas turbines speeds are measured in percent of what they can/should run when full out.

    As to your question... if you're in Texas you still have a long ways to go...

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    1. You are right about a long ways to go, especially in west Texas.

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  2. Replies
    1. Yes, in relation to the road you are driving on but what about to your position in the universe??? You are moving, the car is moving, the earth is moving, the solar system is moving, the galaxy is moving, and the universe is moving. If you take all those into account, you are probably moving pretty fast.

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    2. What if the universe is just a figment of our imagination. I'd get dizzy too if I thought about how fast I might be moving.

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    3. And maybe we are all just characters in a computer animation. But, we all can look up and see the stars and other blotches of light, so I must surmise that they are real. Then when I look through my 16" dia. telescope, I am certain they are real.

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    4. I think Gypsy's reply is right on the money!

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    5. I am always open to what Gypsy has to say, and that goes for all of you.

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  3. Too difficult of a question for me Dizzy :-(

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    1. That question was just supposed to make you laugh. No answer required.

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  4. Think I'll just stick to my old 45 RPM records.....Now don't go confusing me any further with any of that 78 or thirty three and a third stuff now ya hear...........

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    1. I remember those old thick 78s that my grandpa played on a wind up Victrola. I had a record player that had the 78 setting along with the 45 and the 33.3 speeds. Am I giving away my age???

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  5. Too early in the morning for me to have a math quiz. But I'll say my car is on cruise control and the speedometer says 65.

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    1. I know what you mean about it being too early.

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