Experiment of December 18, 2024:

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Solution video:

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Experiment:

Question:

What does she observe, when she places seven tacks on the edge of the glass with the tip pointing upwards on the surface of the water?

A) The tacks all move to the edge of the glass. They seem to repel each other.

B) The tacks join together. They appear to minimise the distance between them.

C) The tacks are evenly distributed on the surface of the water.

D) The tacks float for a maximum of 5 seconds and then sink to the bottom.