Deformable objects can accurately be simulated by using the Finite Element Method. For the finite element method, tetrahedrons are used as finite elements since it is the simplest object that can represent a volume. Physically accurate material constants can be put in to simulate different materials and is done by changing the Young's modulus and the density of the material. The deformable object vibrates when it has collided with another object and these vibrations are represented as velocities of a triangle surface and from these changes in velocities, pressure for each face is calculated and used for calculating the sound.
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