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I Just Dont Get It

  1. Sep 7, 2006 #1
    I Just Dont Get It!!!!!

    Its my second day of physics and I have no idea whats going on -_- Its so riduculous We've started converting units and Im just completly lost I have 6 problems for homework and Im basically screwed :_[. Can someone please guide me through one or two of them? some of them are 286.6mm, 760mg, and 60.0ps please guide me through one or two :_[.
  2. jcsd
  3. Sep 7, 2006 #2


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    It seems like you are working with SI (MKS) units.

    If so, is one supposed to convert each unit to its SI basis. For example, mm = millimeter, and the prefix 'milli' means 1/1000 th, or one-thousandth, and 1 mm = 1/1000 m = 0.001 m. The prefixes take the place of many 0's or scientific notation.

    Another example, kg, which is kilogram. The prefix 'kilo' means 1000, and 1 kg = 1 kilogram = 1000 grams.

    In the first example - 286.6 mm = 286.6/1000 m = 0.2866 m.

    See - http://physics.nist.gov/cuu/Units/prefixes.html

    and http://en.wikipedia.org/wiki/SI

    and this is useful with some examples -

    a useful calculator

    Hyperphysics is a good general site -

    Good for overchecking calculations
    Last edited: Sep 7, 2006
  4. Sep 8, 2006 #3
    One thing to remember also is the concept of 1; that anything divided by itself is 1. 1 foot/12 inches = 1. And that when you muliply 'anything' by 1 the 'anything' does not change. Then it is simply a matter of manipulating the units in the numerator or demominator.
  5. Sep 8, 2006 #4
    thats because you're dividing by 12 inches/ 1 foot so the feet cancel out.
  6. Sep 8, 2006 #5
    Unit conversion

    Here's a site on dimensional analysis. http://www.chem.tamu.edu/class/fyp/mathrev/mr-da.html" [Broken]

    Good luck!
    Last edited by a moderator: May 2, 2017
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