The secret third option: looking at the picture on the left; going straight through the donut through the middle in the vertical direction.
Although now that I saw it, I still think the original left picture is the correct answer. Even through the middle vertically as I mentioned, the centre of gravity would be the same, would it not?
Left is correct. The center of mass of a donut is inside the hole, which is “outside the donut”.
This may seem unintuitive, but the center of mass of an object does not have to be inside the object.
This is the mechanism behind these toys:
The wings of the bird and poles of the clown extend below the main body, but are weighted so that’s where most of the weight is. So the center of mass is below the main body, so it will easily balance on the main body. However, your eyes will naturally focus on the main body, which would be unstable without the extra weight hanging off the side, making the balancing look surprising.
The secret third option: looking at the picture on the left; going straight through the donut through the middle in the vertical direction.
Although now that I saw it, I still think the original left picture is the correct answer. Even through the middle vertically as I mentioned, the centre of gravity would be the same, would it not?
Left is correct. The center of mass of a donut is inside the hole, which is “outside the donut”.
This may seem unintuitive, but the center of mass of an object does not have to be inside the object.
This is the mechanism behind these toys:
The wings of the bird and poles of the clown extend below the main body, but are weighted so that’s where most of the weight is. So the center of mass is below the main body, so it will easily balance on the main body. However, your eyes will naturally focus on the main body, which would be unstable without the extra weight hanging off the side, making the balancing look surprising.
I really like this example too: