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An infinitely long thin non-conducting wire is parallel to the z-axis and carries a uniform line charge density λ . It pierces a thin non-conducting spherical shell of radius R in such a way that the arc PQ subtend an angle 120º at the centre O of the spherical shell, as shown in the figure. The permittivity of free space is ∈ 0 . Which of the following statements is (are) true? 120º R O Q P λ Z

1. The electric flux through the shell is 3 R λ / ∈ 0
2. The z-component of the electric filed is zero at all the points on the surface of the shell
3. The electric flux through the shell is 2 R λ / ∈ 0
4. The electric field is normal to the surface of the shell at all points

Correct answer: The electric flux through the shell is 3 R λ / ∈ 0

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