ABSTRACT
This chapter considers physical problems related to two-dimensional flexible surfaces called membranes. It examines cases where the membrane interacts with the material in which it is embedded and is thus subject to external forces such as driving forces or friction. Examples of membranes include drum heads, flags, trampolines, biological barriers such as cellular membranes. If the membrane is embedded in a material which produces a drag on the motion of the membrane such as the case for biological membranes, which are normally immersed in a liquid environment, a friction term must be added to Equation. Equation gives the evolution of free oscillations of a circular membrane when boundary conditions are homogeneous. In the case of axisymmetric oscillations the solution of the nonhomogeneous equation becomes simpler.
