Why Metal Feels Colder Than Wood

A metal spoon and a wooden spoon have been sitting in the same kitchen all night. When you pick them up, the metal one feels colder. Does that mean it actually has a lower temperature? Usually, no. The difference lies in how quickly heat moves.

If both spoons have been away from sunlight, heaters and other heat sources long enough, they will be close to room temperature. In a typical cool room, your hands are warmer than either spoon. When you touch one, heat moves from your skin into the object.

Metal allows heat to travel through it easily. It quickly carries heat away from where your fingers touch it, spreading that heat through the rest of the spoon. Your skin loses heat quickly, so the spoon feels cold. Wood slows this movement. The small area under your fingers warms up, but heat does not spread through the wood as easily. Your skin therefore loses heat more slowly.

Thermal conductivity—a material's ability to carry heat—explains other familiar experiences. A tile floor often feels colder than a rug in the same room because the tiles carry heat away from your bare feet faster. The rug, including the air held between its fibers, slows that movement.

The same principle helps explain why a cloth can slow the melting of an ice cube. The cloth does not create cold. Instead, it slows the movement of heat from the warmer surroundings into the ice.

There are limits to what touch can tell you. An object in direct sunlight may actually be warmer than one in the shade. If an object is hotter than your skin, heat moves towards your hand rather than away from it. Do not test hot objects by touching them.

Your skin is useful for noticing heat moving, but it is not a reliable thermometer. Something that feels colder is not always at a lower temperature.