Experiment of December 13, 2016:

The time to submit an answer is over. You can now view the solution of the experiment.

Solution video:

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Experiment:

Question:

What das Ms. Santa see when she moves her thumb slowly upwards between eye and cardboard?

A) She sees the hole get darker, and it seems to move from the top towards the bottom.

B) She sees the hole get darker, and it seems to move from the bottom towards the top.

C) She sees the hole get darker, and it seems to move from left to right.

D) She sees the hole get darker, and it seems to move from right to left.