Trailer swing while backing and position of tandems?

I appreciate the kind words, but I’m not that deep, LOL.. it’s just basic physics. For every action there is an equal and opposite reaction, and all that.

 

Saying for every action there is an equal and opposite reaction does not explain this.

It sounds like you are just like me lol-----I don't know why the fact that the only part of the trailer that touches the ground is the tandems makes the tandems the pivot point. I just intuitively know that it is.

I bet a physicist could actually describe the reasoning explicitly though.

 

Well a dead clock is even right twice a day lol.....pretty soon swift will be correct ..haha yeah right

 

Well that came across just a tad rude.

It’s not that “deep” of a concept.

Hands on an analog clock face does the very same thing. The long portion of the arm moves from 12 to 1 while the short portion moves from 6 to 7.

One is moving to the left (from the drivers seat position) while the back end swings to the right.

As mentioned a few times above, it IS just a simple pivot point because where the tires come into contact with the ground is where the trailer will pivot.

 

Why does the fact that the tandems are on the ground make the tandems the pivot point?

 

???

You gotta be trollin

 

Uh because they are what react to your steering inputs, just like a see saw responds to a kid sitting on one side then raises up the other side.......they just simply are thats all that's needed to know...why be rude to others who simply don't care about the reason the tandems are the pivot point? Doesn't make you some deep philosophical human for asking lmao.........

 

I went back to reread the OP to see if I was missing something and was possibly answering the wrong question. In doing so I came across your comment above.

In the above pencil and fingers example you agree with the up/down (opposite directions) movement of the pen where one finger is acting as the pivot of the pen movement while the other finger is causing the movement of the pen in opposite directions.

It’s the very same example except instead of the movement being up/down (opposite directions) it’s left/right. And instead of two fingers you have the tandems replacing one finger as the pivot and the truck replacing the finger simply providing movement. How the truck is connected to the trailer doesn’t matter.

Basically take the pen example and lay it on its side and you change the up/down movement to the left/right movement called trailer swing.

Simple. Right?

 

I could turn this around on you. Why should others who simply don't care about the reason the tandems are the pivot point be rude to me for asking? They could just exit the thread without responding.

 

Let's say that someone is in a hypothetical situation where they are pulling a trailer without trailer wheels over ice. So there are no tandems. The ice has parking lanes on it. Would you still have trailer swing? If you drive the tractor-trailer (without trailer wheels) forward and turn the steering wheel to the left as you are pulling forward out of the parking spot, would the rear of the trailer swing to the right?