Phys 461/561
Fall 2009
Worksheet #20
Monday, November 30, 2009
Name
Questions (5 pts):
Consider vibrations of a circular drumskin of radius a. It is known that:
(i) Its circumference is held fixed in the plane at all times
(ii) Initially, at time t = 0, the displacement from the equilibrium u is a function of
only
(iii) Initially, at time t = 0, the velocity is zero.
Based on the information above, right down boundary and initial conditions (which we
will use) together with the wave equation of motion.