libbox2d-dev binary package in Ubuntu Xenial amd64

 2D rigid body simulation library for games. Programmers can use it in
 their games to make objects move in believable ways and make the world
 seem more interactive. From the game's point of view a physics engine is
 just a system for procedural animation. Rather than paying (or begging)
 an animator to move your actors around, you can let Sir Isaac Newton do
 the directing.
 .
 This package contains the development libraries and headers.

Source package