What is maximal force?

That would be a force that is applied at maximum power.

Nuclear force.

Yes.

Velocity is continually changing direction if not speed. This means an orbiting object is accelerating and the direction of acceleration is toward the center. In fact, centripetal means "center...

No, the magnitude of the resulting force when forces are combined is at MOST equal to the sum of forces, this is when they are all in the same direction. Else its magnitude will always be less than...