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I A question about units in equation: Dimensional analysis

  1. Oct 4, 2018 #1
    This question is about the matching the unites in an equation.

    The equation for an electron mobility is given by m^2/V.S.
    However substituting the units in the equation, doesn't yield the unit of mobility [m^2/V.S]. I have done the simplification using mks units and didn't come up to m^2/V.S. Have a look at the attached file, and help is appreciated.


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  2. jcsd
  3. Oct 4, 2018 #2


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    Welcome to PF.

    Dimensional analysis is the truth. The equations may be wrong, or you may be confusing derived units with the fundamental MKSA system.

    Try to reduce everything to MKSA. Avoid V, which is = M⋅L2⋅T−3⋅I−1

    An electron has charge, where does that appear in the equation with voltage?
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