2. Sample Papers
  3. NEET

NEET Sample Paper NEET Sample Test Paper-42

  • question_answer
    From a circular disc of radius R and mass 9M , a small disc of radius \[\frac{R}{3}\] is removeThe moment of inertia of the remaining disc about an axis perpendicular to the plane of the disc and passing through 0 is:

    A) \[4M{{R}^{2}}\]                     

    B) \[\frac{40}{9}M{{R}^{2}}\]

    C) \[10M{{R}^{2}}\]                   

    D) \[\frac{37}{9}M{{R}^{2}}\]

    Correct Answer: D

    Solution :

    \[\frac{{{m}_{1}}}{{{A}_{1}}}=\frac{{{m}_{2}}}{{{A}_{2}}}\] \[\frac{9M}{\pi {{R}^{2}}}=\frac{m}{\pi {{\left( \frac{R}{2} \right)}^{2}}}\] \[{{\operatorname{m}}^{2}}=M\] \[{{\operatorname{I}}_{rem}}={{I}_{wide}}-{{I}_{removed}}\] \[=\frac{1}{2}9M{{R}^{2}}-\left[ \frac{1}{2}M{{\left( \frac{R}{3} \right)}^{2}}+\frac{1}{2}M{{\left( \frac{2R}{3} \right)}^{2}} \right]\] \[{{\operatorname{I}}_{rem}}=4M{{R}^{2}}\]


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