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A hollow, conducting sphere is initially uncharged. A positive charge, +q1, is placed inside the sphere (at the center). Then, a second positive charge, +q2, is placed near the sphere but outside it.
Which of the following statements describes the net electric force on each charge?
1-There is a net electric force on +q2 but not on +q1.
2-There is a net electric force on +q1 but not on +q2.
3-Both charges are acted on by a net electric force with the same magnitude and in the same direction.
4-Both charges are acted on by a net electric force with the same magnitude but in opposite directions.
5-There is no net electric force on either charge.
Attempt at a solution
I know that for a charged hollow spherical conductor, the charge is distributed on both the inner and outer surface of the conductor, and the net electric field in the material of the conductor is zero, also the net electric field inside the cavity is zero, and the net eelectric field in a point close to the outer surface is δ/ε0
but in this case there is a point charge at the center of the cavity, and the net electric field inside the cavity must has a nonzero value (due to the point charge).
i thought that both of the charges may cause the spherical conductor to be charged through induction, so the electric field due its charge inside the cavity is zero, and hence choice (1) will be relevant, but i am not sure.
i thought also that if the spherical conductor will remain uncharged, so there will not be a charge distribution in its surface, and the only remaining thing is the coulomb force between the two charges acting on each other, so choice (4) will be relevant.
please help
Which of the following statements describes the net electric force on each charge?
1-There is a net electric force on +q2 but not on +q1.
2-There is a net electric force on +q1 but not on +q2.
3-Both charges are acted on by a net electric force with the same magnitude and in the same direction.
4-Both charges are acted on by a net electric force with the same magnitude but in opposite directions.
5-There is no net electric force on either charge.
Attempt at a solution
I know that for a charged hollow spherical conductor, the charge is distributed on both the inner and outer surface of the conductor, and the net electric field in the material of the conductor is zero, also the net electric field inside the cavity is zero, and the net eelectric field in a point close to the outer surface is δ/ε0
but in this case there is a point charge at the center of the cavity, and the net electric field inside the cavity must has a nonzero value (due to the point charge).
i thought that both of the charges may cause the spherical conductor to be charged through induction, so the electric field due its charge inside the cavity is zero, and hence choice (1) will be relevant, but i am not sure.
i thought also that if the spherical conductor will remain uncharged, so there will not be a charge distribution in its surface, and the only remaining thing is the coulomb force between the two charges acting on each other, so choice (4) will be relevant.
please help