The electrostatic field of a point charge and an electrical dipole in   the presence of a conducting sphere
  We evaluate the electrostatic potential and the electrostatic field created by a point charge and an arbitrarly oriented electrical dipole placed near a grounded perfectly conducting sphere. Induced surface charge distributions as well as electrostatic energy, force and torque associated with this configuartion are fully discussed. Possible variants of the problem are also discussed. 
F C Santos and A C Tort