All things that move need a pressure to make them move, all pressure requires a pushing force, so therefore "pull" is not force in its self?
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All things that move need a pressure to make them move, all pressure requires a pushing force, so therefore "pull" is not force in its self?
There has to be a pressure (push) to start anything to move, so "pull" is not a force.
If you have a loop in the end of the rope you just link your hand through it and then you don't need to push on anything. A rope is actually a perfect example of something that exerts a force by pulling. Something pulls the rope and it goes tight due to the force of tension in it, as it pulls whatever the object is. The tension in the cables is what enables a suspension bridge to hold up the roadway.
Where you have a point is, going back to your pressure idea, that when vacuum cleaner "sucks" up dust, it does not pull on it. It just takes away the atmospheric pressure that is normally exerted from all sides on objects, and that pressure imbalance is what causes the dust to move into the suction tube.
Try moving anything without a pushing pressure, "pulling" is a description of the action. You need to add pressure inside the loop, in order for the "pull" to take place.
If all you mean is that any pull involves a push (part of the rope is pushing against part of the loop when the cart is being pulled) then that’s another topic for debate. In physics “a force is any interaction that, when unopposed, will change the motion of an object”.1 And “pulling the cart” simply means that the vector of the applied force of “that small portion of rope against that small portion of the loop” is aimed away from the cart as opposed to being aimed towards it.
1 https://en.wikipedia.org/wiki/Force [my emphasis]
"Pull" is the result of a pushing force, "pull" itself is not a force.
I don't see what is hard to understand here, something has to push against whatever is being "pulled" at the very source, nothing moves without pressure and you cannot have pressure without a pushing motion. Try it yourself.
I've had the same idea that pulls do not exist as forces, that they are really pushes in disguise (for example, pulling on a door is really pushing the handle/knob towards you).
If we define "push" as exerting a force in the opposite direction from yourself and "pull" as exerting a force in the direction of yourself, then gravity is always a pull, as well as electric forces between opposite charged objects.
In the case of a trailer, the net force on the trailer from the rope is in the direction of the rope, so is a pull. But the end of the rope is pushing on the hook of the trailer.
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