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    • Thread Starter
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    I have a calculation and the units are square root of 9 km^3 s

    what would the answer be ? im thinking 3 km^2 s
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    What are the units?
    • Thread Starter
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    its an algedra equation, I have brought it down to
    d = square root of 9 km^3 s

    so 9 kilometers^3 per second
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    This really is nonsense gibbyni. Do you want to explain what you are trying to achieve?
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    ok lets say when doing e=mc^2
    Mass 1kg
    C (speed of light) is 3.0 x 10^8 m s^-1

    e = 1 kg x (3.0 x 10^8 m s^-1)^2

    e = 1 kg x 9.0 x 10^8 m^2 s^-2

    result is 9 x 10^16 kg m^2 s^-2

    its the bits about kg m^2 s^-2 that im talking ablout changing, since when the m s^-1 was squared it changed to m^2 s^-2.

    So im needing to know what happens to my km^3 s when I find the square roof of my equation.
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    Well, looking at your units should tell you that taking the square root of this gives you an unphysical quantity. So why worry about it?
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    (Original post by gibbyni)
    ok lets say when doing e=mc^2
    Mass 1kg
    C (speed of light) is 3.0 x 10^8 m s^-1

    e = 1 kg x (3.0 x 10^8 m s^-1)^2

    e = 1 kg x 9.0 x 10^8 m^2 s^-2

    result is 9 x 10^16 kg m^2 s^-2

    its the bits about kg m^2 s^-2 that im talking ablout changing, since when the m s^-1 was squared it changed to m^2 s^-2.

    So im needing to know what happens to my km^3 s when I find the square roof of my equation.
    Ok I understand dimensions - I want to know why you think you need to take \sqrt{km^3 s} because, if this is a physics question, you have certainly made a mistake. As Zhen Lin said the answer you obtain is not a physical quantity.
 
 
 
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