In Unity, the behavior of an object that is based on physics is defined separately from its mesh (shape), materials (UV texture), and the renderer properties. The items that play into physics include the following:
The Rigidbody component
The Collider component
The Physic Material
The project Physics Manager
Basically, physics (in this context) is defined by the positional and rotational forces that affect the transform of an object, such as gravity, friction, momentum, and collisions with other objects. It is not necessarily a perfect simulation of physics in the real world because it's optimized for performance and separation of concerns to facilitate animation. Besides, virtual worlds might just need their own laws of physics that aren't found in our God-given universe!
Unity 5 integrates the NVIDIA PhysX engine, a real-time physics calculation middleware, which implements classical Newtonian mechanics for games and 3D applications. This multiplatform software is optimized...
