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:
- Rigidbody: Enables the object to act under the control of the physics engine, receive forces and torque to move in a realistic way
- Collider: Defines a simplified, approximated shape of the object used for calculating collisions with other objects
- Physic Material: Defines friction and bounce effects of colliding objects
- Physics Manager: Applies global settings for 3D physics for your project
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...