How do I make tip of the boat ramp physics controlled?

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The part of the ramp circled in red (img 1) is physics controlled. Once the ramp is lowered, the part of the ramp will collide with the ground and move as such, basically realistic (img 2). Ive been visiting a group that does this and wonder how I could do it also. How can I achieve this?

For the end of the ramp , build it with hindge contrants , or you could have a rod going into cylindar sockets that allow it to pivor on the inner edges

And make the parts almost massless so the move easier