# Frequency modes of the rectangular shell

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The shapes of three natural modes having the frequencies $\omega_1, \omega_2, \omega_3$ of the rectangular shell are presented in the figure. The exciting pressure $p(t)$ applied uniformly all over the one side of the shell has the form $p(t) = Pe^{jωt}$.
Make a sketch of the normal displacement of the gravity point of the shell against frequency, if the excitation frequency varies within bounds $0.5\omega_1< \omega <2\omega_1$ and static displacement of that point equals to $u_0$.

Links to photo of frequency nodes (sorry for low quality)->1 .

Can somebody help me and tell me how i should get started?

* The image is also not clear.  I guess for $\omega_1$ the only nodes are at the edges of the shell, for $\omega_2$ there is a node at the centre of the shell but I cannot make out the mode shape for $\omega_3$.