JEE Main & Advanced Physics Mathematical Tools, Units & Dimensions JEE PYQ - Mathematical Tools Units and Dimensions

  • question_answer
    Which of the following units denote the dimensions\[[M{{L}^{2}}/{{Q}^{2}}],\]where 0 denotes the electric charge?                           [AIEEE 2006]

    A) \[Wb/{{m}^{2}}\]

    B) Henry (H)

    C) \[H/{{m}^{2}}\]

    D) Weber (Wb)

    Correct Answer: B

    Solution :

    [b] Magnetic energy stored in an inductor
    \[=\frac{1}{2}L{{i}^{2}}=\frac{L{{Q}^{2}}}{2{{t}^{2}}}\]
    (\[L\to \]inductance, \[i\to \]current)
    Energy has the dimensions\[[M{{L}^{2}}{{T}^{-2}}]\].
    Equate the dimensions, we have
    \[[M{{L}^{2}}{{T}^{-2}}]=(Henry)\times \frac{[{{Q}^{2}}]}{[{{T}^{2}}]}\]
    \[\Rightarrow \]\[[Henry]=\frac{[M{{L}^{2}}]}{[{{Q}^{2}}]}\]


You need to login to perform this action.
You will be redirected in 3 sec spinner