The work deals with an electro-optical study of chiral nematic liquid crystals, S-(+)-4-(2- methybutyl)phenyl 4-decyloxybenzoate (CE6) and Cholesteryl Nonanoate (CN), a cholesteric polymer, C4745, and a 90%CE6-10% C4745 mixture through the use of optical activity and light scattering techniques. An expression for the optical activity in chiral nematic liquid crystals has been derived for zero field. This derivation represents an extension of the present theory of optical activity in chiral nematics.Dynamic light scattering studies were performed on various concentrations of CE6-...