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Vijay posted an Question
March 23, 2021 • 12:22 pm 30 points
  • IIT JAM
  • Mathematics (MA)

Where have i made a mistake? the answer is 18pi.

please don't solve using the divergence theorem.

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  • Alka gupta

    apply GD theorem.....

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    What's wrong with my calculation?

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    here you calculate only on one surface....you have to calculate on all surfaces which is included in bounded surface....so that's why you not got correct ans

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    Deepak singh 1 best-answer

    Refer attached answer is 18π

    cropped4148986858155297140.jpg
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    What's wrong with my calculation?

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    because in question , it is said that S is entire surface . But you have calculated on surface x^2+z^2=9 only . You have to calculate on all bounded surface of region .( y= 0 plane , y=8 plane etc.)

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    solution will become longer if we do by solving integral on all surface . So its better to use divergence theorem here .

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    Thank you Deepak sir!

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