Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

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

    A=√(R/TY)

    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

    Mark44

    User Avatar
    Insights Author

    Staff: Mentor

    Both your notation and explanation are ambiguous.

    Is the expression on the right side this?
    [tex]\sqrt{\frac{R}{TY}}[/tex]
    or this?
    [tex]\frac{\sqrt{R}}{TY}[/tex]
     
  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
    [tex]\sqrt{\frac{R}{TY}}[/tex]

    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
    [tex]\sqrt{\frac{m^3}{m}}[/tex]

    which is
    [tex]\sqrt{m^2}[/tex]

    or, more simply m
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Working out the units?
Loading...