Find the force affecting the Y axis of an object. Logic Bricks.

How can I do that?

You can get the force applied at the last physics tick with object.getReactionForce().
EDIT*
Nope, nevermind, not implemented yet.

yet *.*So it will only be possible through python and it´s not possible to get it through logic bricks.

Why do you need this information? I have a feeling what you are wanting to do can be handled without arbitrarily accessing applied force. Objects don’t really carry the force around with them, it is used to change their velocity, and then it is thrown away. You could probably get what you want by knowing the velocity of the object.

What do you intend to do? You could instead measure the speed of the object (which is slightly different to your request).

Well in any case, the magic number for BGE appears to be 30. force = mass * v * 30. If you apply 30 force units to an object with 1 mass, its maximum velocity without any damping forces should be 1.

So force = (object.mass * object.worldLinearVelocity.y * 30)

But if you have damping forces on, or the object is sliding across a surface, this will not work.

Well now I use linear velocity instead of force because it’s easier to make the things I want that way. I wanted to use force so I can control my speed and because the transition of speed is smooth. Now that I’ve found out how to do the same with linear velocity I don’t need force.