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

  • question_answer
    A physical quantity P is described by the relation \[P={{a}^{1/2}}\,{{b}^{2}}{{c}^{3}}{{d}^{-4}}\]
    If the relative errors in the measurement of \[a,\,b,\,c\] and d respectively, are 2%, 1%, 3% and 5%, then the relative error in P will be – [JEE Online 09-04-2017]

    A) 12%

    B) 8%

    C) 25%

    D) 32%

    Correct Answer: D

    Solution :

    [d]  \[\frac{\Delta P}{P}=\frac{1}{2}\,\frac{\Delta a}{a}\,+2\,\frac{\Delta b}{b}\,+3\,\frac{\Delta c}{c}\,+4\,\frac{\Delta d}{d}\]
                \[=\frac{1}{2}\,\times 2+2\times 1+3\times 3+4\times 5\]
                \[=32%\]


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