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The excess (equal to number) number of e...

The excess (equal to number) number of electrons that must be placed on each of two small spheres spaced `3cm` apart with force of repulsion between the spheres of be `10^(-19)N` is

A

25

B

225

C

625

D

1250

Text Solution

Verified by Experts

The correct Answer is:
C
`F=1/(4 pi epsilon_(0)) (q_(1)q_(2))/(r^(2))` and q=ne
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NARAYNA-ELECTRIC CHARGES AND FIELDS-EXERCISE -2 (H.W)
  1. Two charge when kept at a distance of 1m apart vacuum have a some forc...

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  2. The excess (equal to number) number of electrons that must be placed o...

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  3. Two small conducting spheres each of mass 9xx10^(-4)kg are suspended f...

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  4. Two point charges of magnitude 4muC and -9muC are 0.5 apart .the elect...

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  5. A charge +q is fixed to each of three corners of a square .On the empt...

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  6. Electrical force between two point charge is 200N, if we increase 10% ...

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  7. N fundamental charges each of charge q are to be distributed as two po...

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  8. A particle A having a charge of 2.0xx 10^(-6) C and a mass of 100 g i...

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  9. Two identical particles of charge q each are connected by a massless s...

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  10. Point charge of 3xx10^(-9)C are situated at each of three corners of a...

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  11. A large flat metal surface has a uniform charge density +sigma. An ele...

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  12. n charges Q,4Q,9Q,16Q…. are placed at distance of 1,2,3….. metre form ...

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  13. Two point charge q(1)=2muC and q(2)=1muC are placed at distance b=1 an...

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  14. A regular pentagon has four charges each +q at four of its vertices. A...

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  15. Two point charges a and b whose magnitude are same, positioned at a ce...

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  16. Find out electridc filed intensity at point A(1,0,2) due to a point ch...

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  17. An electric dipole consists of two opposite charges of magnitude 1muC ...

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  18. An electric dipole is formed by two particles fixed at the ends of a l...

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  19. For an electric dipole consisting of a positive and equal negative cha...

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  20. Two equal charges q of opposite sign are separated by a small distance...

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