Have you seen this:



There are 2 uniformly charged spheres (call them charge clouds):






Sphere 1: volume charge density: P, radius: 1, center: (0,0,0).
Sphere 2: volume charge density: -P, radius: 1.5, center: (1,1,1).

Find the electric field in their region of intersection.
Answers welcome.

16 comments:

  1. come on people, or is it really 'too easy'?

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  3. i tried 'superposition' and got

    "E= P1*D1/ 3e + P2D2/3e "

    where, P= modulus of volume charge density
    D= dist of respective centres from the plane of intersection
    e= epsilon........
    pls tell if its right( m not too sure)

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  4. sambhav it is easy
    specially if uve done a similar questn b4
    d only trick i can think of is to do it with vectors

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  6. the answer is

    rho*c1*c2/3*eps?

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  7. correction-- , not C1*C2..but C1C2(vector)

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  8. anonymous is correct
    @shaan, had P1 and P2 been their 'actual' densities, you'd have been correct
    E= P1*D1/ 3e + P2D2/3e would have become P/3e(D1-D2), which becomes P(C1C2)/3e

    D1 and D2 are position vectors of the any point in the region of intersection from the centers of the spheres, and by vector triangle, D1-D2 is the vector C1C2

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  9. and what if i say, there is just a single sphere of given charge density, with another spherical 'cavity' completely inside it?

    also, do these apply to gravitation as well?

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  10. i think this is a new 'too easy' record.

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  11. cud u draw the electric field lines here

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  12. thanks sambhav, i missed that..

    for single sphere , it wud remain same..
    ie E=P(C1C2)/3e

    also, this shud apply to gravitation, by the perfect analogy..
    whatsay??

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  13. yeah. only the constants vud change for gravitational force

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  14. the first case wouldn't, we don't actually have poles in gravitation, although the second would.

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  15. obviously sambhav

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