How we sense temperature

Two blocks...

The setup: Two identically painted black blocks. You felt them both. The unanimous vote was that the block on the right felt warmer.

This is already surprising: Both blocks had been stored on the same shelf in SC 008 for several months. They were both in contact with the same shelf and the same air. This should have been plenty of time for them to both reach the same temperature as the air and shelf. They should have been at the same temperature, yet one block "felt warmer" than the other.

Place ice on both blocks

We placed chunks of ice on both blocks. On which block will the ice melt faster? Towards the end of class,

...there was still ice on the right "warmer" block, but it had long ago melted on the left "colder" block

The left block was made of metal. Metals conduct electricity (electrons move very easily). Metals are good conductors of heat!
$\Rightarrow$ As the cold ice cube touches the metal, the "cold" from the ice does not stay close to the surface, but quickly gets spread out among all the molecules in the whole block, so the surface of the metal remains close to the original temperature of the block.

As a warm tongue touches a cold metal pole, the temperature of the surface stays at the original (outdoor) temperature of the pole!

Wood is a rather poor conductor of heat. Or if you prefer, Wood is an excellent insulator.
$\Rightarrow$ As the cold ice touches the surface of wood, it cools down a small number of wood molecules near the surface, and the cold does not travel easily away to other parts of the block. So, the cold is shared by just a few molecules at the surface, which rapidly approach the temperature of the ice (not the rest of the block). Because heat travels very s l o w l y from the rest of the wood (to the surface). the surface can rapidly change to the temperature of whatever is touching it regardless of the temperature of the rest of the block.

It's safer to lick a stick on a cold day (or a tree!) because the surface of the wood will rapidly warm to the temperature of your tongue, rather than the temperature of the rest of the wood.