Table of Contents
ISRN Mechanical Engineering
Volume 2011, Article ID 597172, 8 pages
Research Article

Gravitational Instability of Rotating Viscoelastic Partially Ionized Plasma in the Presence of an Oblique Magnetic Field and Hall Current

1Department of Mathematics, Faculty of Education, Ain Shams University, Heliopolis, Roxy, Cairo 11757, Egypt
2Department of Physics, Faculty of Education, Ain Shams University, Heliopolis, Roxy, Cairo 11757, Egypt

Received 29 January 2011; Accepted 17 March 2011

Academic Editor: P. M. Mariano

Copyright © 2011 M. F. El-Sayed and R. A. Mohamed. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The gravitational instability of a rotating Walters Bโ€ฒ viscoelastic partially ionized plasma permeated by an oblique magnetic field has been investigated in the presence of the effects of Hall currents, electrical resistivity, and ion viscosity. The dispersion relation and numerical calculations have been performed to obtain the dependence of the growth rate of the gravitational unstable mode on the various physical effects. It is found that viscosity and collision frequency of plasma have stabilizing effects, while viscoelasticity and angular frequency of rotation have destabilizing effect; the electrical resistivity has a destabilizing effect only for small wavenumbers; the density of neutral particles and the magnetic field component in z-direction have stabilizing effects for wavenumbers ranges ๐‘˜<5 and ๐‘˜<10, respectively; the Hall current has a slightly destabilizing effect. Finally, the inclination angle to z-direction has a destabilizing effect to all physical parameters.