If sound is emitted inside a thin-walled titanium container...?

Question

are the walls actually deformed as they act as a membrane ?
Similarly, puzzling, if you hear a cicadee chirp outside a glass window, it is generating enough energy to vibrate your window glass, right ? I'm asking bec. I dropped out of h.school prior to acoustics, and it seems puzzling that such heavy objects act as membranes w. so little energy input.

Answer 1

The answer to both questions is yes. You can listen in to a conversation inside a building by bouncing a laser beam off the outside of a window, getting an interference pattern from the vibrating window, converting the changing amplitude of the light into an electric signal, amplifying it and feeding it to a loudspeaker. Your titanium container could be used as an eavesdropping device by bouncing microwaves off it from a distance and doing the same thing with the interference pattern. To shield off sound, you need something soft and dense. Lead sheet is often used as an engine cover on boats for this purpose. A good question.