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Question
A uniformly charged conducting sphere of 2.4 m diameter has a surface charge density of 80.0 μC/m2.
- Find the charge on the sphere.
- What is the total electric flux leaving the surface of the sphere?
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Solution
Given: d = 2.4 m
R = `2.4/2` m = 1.2 m
σ = 80.0 μC/m2
= 80 × 10−6 C/m2
(a) As σ = `q/(4pir^2)`
so, q = 4πr2 × σ
= 4 × 3.14 × (1.2)2 × 80 ×10−6
= 1446.9 ×10−6
or q = 1.45 × 10−3 C
(b) Φ = `q/ε_0`
= `(1.45 xx 10^-3)/(8.85 xx 10^-12)`
= 0.1638 × 109
= 1.64 × 108 N C−1 m2
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