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Working out the units?

  1. Nov 8, 2011 #1
    I am having a problem finding the correct SI unitsfor the quantity A?

    In the equation


    That is A equals the square root of R divided by TY

    (not to good showing workings on the computer sorry)

    , the SI units of the quantity R are kg m^3 s^–2, the SI units of the quantity T are kg and the SI units of the quantity Y are m s^–2. What are the correct SI units for the quantity A?
    Last edited: Nov 8, 2011
  2. jcsd
  3. Nov 8, 2011 #2


    Staff: Mentor

    Both your notation and explanation are ambiguous.

    Is the expression on the right side this?
    or this?
  4. Nov 8, 2011 #3
    The first one R/ty all square root. Do apologise for the bad format
  5. Nov 8, 2011 #4
    Then, the units of A are meters.
  6. Nov 9, 2011 #5
    To clarify gsal's answer...

    You have the expression

    Simply, insert the units for each variable (in place of the variables):
    [tex]\sqrt{\frac{\frac{kg\cdot m^3}{s^2}}{(kg)(\frac{m}{s^2})}}[/tex]

    and simplify...
    [tex]\sqrt{\left(\frac{kg \cdot m^3}{s^2}\right) \left(\frac{s^2}{kg \cdot m}\right)}[/tex]

    kg and s2 cancel out, leaving

    which is

    or, more simply m
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