Question

Two concentric metallic spherical shells of radii R and 2R are given charges Q1 and Q2 respectively. The surface charge densities on the outer surfaces of the shells are equal. Determine the ratio Q1 : Q2. [CBSE (F) 2013]

January 14, 2024

Answer

Surface charge density σ is same.

∴ Charge Q₁ = 4πR²σ

and Charge Q₂ = 4π(2R)²σ

∴ Q₁ : Q₂= 4πR²σ : 16πR²σ = 1 : 4

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