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JEE MAIN 2019
12-04-2019 S2
Question
Let a total charge 2 Q be distributed in a sphere of radius R, with the charge density given by (r) = kr, where r is the distance from the centre. Two charges A and B, of –Q each, are placed on diametrically opposite points, at equal distance, a, from the centre. If A and B do not experience any force, then :
Select the correct option:
A
$a=\frac{3 R}{2^{1 / 4}}$
B
$\mathrm{a}=\mathrm{R} / \sqrt{3}$
C
$a=2^{-1 / 4} R$
D
$a=8^{-1 / 4} R$
✓ Correct! Well done.
✗ Incorrect. Try again or view the solution.
Solution
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