Two metal spheres of radii R and 2R have same uniform surface charge density σ. They are brought in contact and separated. The new charge densities on them will be:
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Two metal spheres of radii R and 2R have same uniform surface charge density σ. They are brought in contact and separated. The new charge densities on them will be:

G1 Physics · Accepted Answer

Step 1: Initial charges are q₁ = 4πR²σ and q₂ = 16πR²σ; total = 20πR²σ. Step 2: On contact potentials equal, giving q′₁/q′₂ = R/(2R) = 1/2. Step 3: Final charges q′₁ = (1/3)(20πR²σ), q′₂ = (2/3)(20πR²σ). Step 4: σ′₁ = q′₁/(4πR²) = 5σ/3; σ′₂ = q′₂/(16πR²) = 5σ/6.