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A thin non-conducting ring of radius R has linear charge density λ = λ_ocosφ, where λ is a constant and φ is the azimuthal angle. find the magnitude of electric fiel strength on the axis of the ring as a function of the distance x from its centre. investigate the obtained function at x>>R.
ans - (λ_oR²)/{4ε_o(x²+R²)^3/2}