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by aap_ 71 days ago
No, around a single axis. if you hold your hand palm up you can rotate in the (vertical) z axis around 360° and get a twist in the arm. another 360° undoes the twist, that's 720° around a single axis.
1 comments

No. The first rotation is along an axis in the direction in which your fingers point. The second rotation is along an axis normal to your palm.
If you're rotating around your fingers you're doing something else, not what i mean. I'm just talking palm up, rotating in the vertical axis, 720°. like the cup dance.