transamz9 wrote:
You really don't understand that a lever creates torque. When you open a door, you are creating torque. When you drive across a bridge with your truck you are creating torque on the bridge. Yes when you drop the hitch of a travel trailer on the hitch the rear wheel becomes the rotational center point.
Here's a little write up with pictures.
Torque and Rotation
You go ahead and stick with the door hinge theory. Door hinges are idle. They neither produce nor use torque. A door closer however uses torque produced by a coil spring to turn a shaft to which a hinged arm is attached to pull the door closed.
When you drop the coupler of a trailer onto the hitch ball, the rear axle of the truck becomes the axis between the ball and front wheels. You seem to be suggesting that the tongue weight produces a rotational force on the rear wheels. Would that be forward or reverse rotational force? Which way will the rig move due to weight on the hitch ball?
