Monday, January 11, 2010

Constant? I think not.

Time and time again I hear (even from professionals): "The acceleration due to gravity is constant (~9.8 m/^s^)," this is simply not so.

First, I would like to say that in order to speak of an acceleration an object must be specified. Therefore, "The acceleration due to gravity is constant," now becomes "The field strength of gravity is constant," but even this well corrected phrase is not to my liking.

Second, the force of gravity obeys Newton's universal law of gravity (in the classical sense) whereby the field strength is constantly being depleted in accordance with an inverse square law. Therefore, "The field strength of gravity is constant," now becomes "The field strength of gravity is approximately constant at short distances to the earth's surface."

All is well with the world.


I would also like to add that with the semester introducing itself more posts will be add to the "Problems" section of the blog. Please view old posts for details.

17 comments:

  1. 大家隨便說,說什麽都好,就是請不要惦惦.............................................

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  2. 生命所經歷的折磨愈多,其所產生的奮鬥力愈大。 ..................................................

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  3. 生存乃是不斷地在內心與靈魂交戰;寫作是坐著審判自己。......................................................................

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