Electrostatics

Question

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Two identically charged pith balls are suspended from the same point by two massless identical threads density of each ball is ρ. If system is immersed in a medium of density σ, balls remain undeflected, then the dielectric constant of medium is

Answer 1

If the balls are suspended in a medium of density σ and the distance between the balls remains same, then the dielectric constant of the medium is given by:

So The dielectric constant of the medium(K) = ρ/(ρ-σ)

So the option 1 is correct