Follow the Face: One Quarter-Turn

Can one dot reveal a cube after it turns? Watch closely... the cube moves, but every mark stays glued to its physical face.

Triangle on top, dot on the front, stripe on the right. A world-fixed axis appears. The camera stays still. The cube makes one quarter-turn forwards as a faint ghost holds the start pose. Follow ONE clue: the front dot travels onto the top. Now confirm a neighbour. The stripe touched the dot before, and still touches it afterwards. It remains on the right. A rigid rotation preserves touching faces and shape. Nothing stretches, swaps sides, or becomes a mirror image. Beware of flat nets and block solids. Faces far apart on a net are not automatically opposite; imagine folding it. An irregular solid may also need supporting cubes hidden behind visible ones. Rotation changes the view, never the construction.

Let's work through an example. A cube shows a triangle on top, a dot on the front, and a stripe on the right. It turns forwards by one quarter-turn. Which option is correct? Option A keeps triangle on top, dot on front, and stripe on right. Option B has dot on top, a blank front, and stripe on right. Option C has dot on top, stripe on front, and a blank right. Option D has triangle on top, a blank front, and dot on right. Track the front dot. As the axis leads the turn, the dot rises with its physical face and lands on TOP... So A is out: its dot never moved. D is out too: its dot moved sideways. Check the touching stripe. It stays on the right beside the dot, so C is out because its stripe has shifted to the front. The old top triangle has turned away. That leaves Option B. Option B is correct.

Remember: track one face through the quarter-turn, confirm a neighbour, and keep every touching relationship and hidden cube fixed. Rotate, do not reflect... and you will spot the matching solid with confidence.