E=∫0R4πϵ01×(x2+Z2)23σ×2πx(dx)×x=2ϵ0σ(1−(Z2+R2)1/2Z)
A uniformly charged disc of radius R having surface charge density σ is placed in the xy plane with its center at the origin. Find the electric field intensity along the z-axis at a distance Z from origin:
Held on 27 Aug 2021 · Verified 6 Jul 2026.
E=σ2ϵ0((Z2+R2)1/21+Z)
E=2ϵ0σ(1+(Z2+R2)1/2Z)
E=2ϵ0σ(1−(Z2+R2)1/2Z)
E=2ϵ0σ((Z2+R2)1+Z21)
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