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Question

A charge of 1.0 × 10-6 μC is located inside a sphere, 1.25 cm from its center. What is the electric flux through the sphere due to this charge? (ε0 = 8.85 × 10-12 C^2/N ∙ m^2)

11 N ∙ m^2/C
It cannot be determined without knowing the radius of the sphere.
8.9 N ∙ m^2/C
0.028 N ∙ m^2/C
0.11 N ∙ m^2/C

Answer 1

Given

Charge , q = 1.0 × 10^-6 μC

                  =1.0 × 10^-12 C

Location of the charge, x =1.25 cm

Permittivity, ε₀ = 8.85 × 10^-12 C²/N ∙ m²

Calculate the electric flux through the sphere due to this charge by using the gauss law

Φ =EA

    =(q/4πε₀ r² )πr²

    =q/4ε₀

    =(1.0 × 10^-12 )/4(8.85 × 10^-12 )

   = 0.0282 N m² C⁻¹

Therefore, the option 3 is correct.  

Comments

this one is certain wrong. The area of the sphere should be 4πr²  

so you should still calculate the flux by q/ε₀

_{which makes} 0.11 N ∙ m^2/C the correct answer