Question

Another easy one:
Wrong-way mercury.
A thermometer is quickly removed from molten tin. At first the mercury goes up, not down! Explain this strange phenomenon.
(it's really physics I know)

Answer 1

Might it be because the thermometer cools very slightly before the mercury, and so the tube contracts which pushes the mercury higher?

Answer 2

Yep.
To quantify this effect, compare the coefficients of thermal expansion for glass and mercury.

Answer 3

very nice question,