Physics Explanation to this experiment?

Question

My experiment is the following:

Firstly, three books (1 inch thick) is needed. Place one book on top of the other book, such that the experiment would be set with two books and the other remaining book 30 inches far from the other books. Then, two meter sticks will be put on top of the books. The sticks should form a V-shape, with the open part of the letter on the double book stack. The mouth of 2 funnels (The large opening) will then be taped together. Place the taped funnels on the narrow part of the V-shape (the corner of the single book stack).

Result:
Instead of expecting that the funnels would slide down due to the slope facing downward, it will climb up the slope.

Ok...well, thats it! I need a good explanation to this experiment...Please help me, the source of this experiment doesnt give a good explanation...Its too short and too narrow and my classmates would probably not understand if I would use it. best one gets 10 points. thanks...

Answer 1

Do this experint on a horizontal table.
Before letting the funnels roll, take a scale and measure the height of the narrow tip of the funnel from the table surface.
Now let the funnel roll. Now measure the height again. You will find that the funnels have actually rolled down, not up.
This happens because of the shape of the taped funnels. The funnels are supported by the V shape at its inclined faces. So as the V shape widens, the funnels move down, when the funnels move down, again the V shape widens, and it goes on like that.
This will give an illusion of the funnels moving up.
This happens only up to a certain slope of the V shape.
In your experiment, try increasing the slope of the V shaped sticks (put 3, 4, then 5 books instead of 2) and see what happens.