How to know the force on a rigidbody 2d?

Unity Engine
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2

Force on any Rigidbody comes in two primary forms:

  1. the force(s) you apply in code

  2. the forces applied by collisions

The former is trivial: it’s your code, go find it.

The latter is provided in the Collision objects given to you by Unity during collision message callbacks.

Since you have provided absolutely nothing in the form of functional code, it’s not possible to say anything more except:

How to report your problem productively in the Unity3D forums:

http://plbm.com/?p=220

How to understand compiler and other errors and even fix them yourself:

If you post a code snippet, ALWAYS USE CODE TAGS:

How to use code tags: Using code tags properly