Suppose that the Faraday concentric sphere experiment is performed in free space using a central charge at the origin, Q₁, and with hemispheres of radius a. A second charge Q₂ (this time a point charge) is located at distance R from Q₁, where R >> a.

(a) What is the force on the point charge before the hemispheres are assembled around Q₁?

(b) What is the force on the point charge after the hemispheres are assembled but before they are discharged?

(c) What is the force on the point charge after the hemispheres are assembled and after they are discharged?

(d) Qualitatively, describe what happens as Q₂ is moved toward the sphere assembly to the extent that the condition R >> a is no longer valid.