Charge in the form of a plane sheet with density ρs = 40 μC/m2 is located at z = -0.5 m. A uniform line charge of ρl = -6 μC/m lies along the y axis. What net flux crosses the surface of a cube 2 m on an edge, centered at the origin?
Charge in the form of a plane sheet with density ρs = 40 μC/m2 is located at z = -0.5 m. A uniform line charge of ρl = -6 μC/m lies along the y axis. What net flux crosses the surface of a cube 2 m on an edge, centered at the origin? Correct Answer 148 μC
Qenc = ∫ρsds
Qnet = Qsurface + Qline
ρs = 40 μ c/m2
ρℓ = -6μ c/m
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Now, the area of the cube is where the sheet lies = 2 × 2 = 4m2
Qsurface = 40 × 4 = 160 μC
Now, for Qline
Qline = ∫ρℓdl
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= ∫(-6) × (2) = -12 μC
∴ Qnet = 160 – 12 = 148 μC
