Why a Metal Spoon Warms Up

Why a Metal Spoon Warms Up

When a metal spoon stirs hot soup, the soup is warmer than the spoon. Energy passes from the soup to the part of the spoon beneath the surface. This transfer of energy caused by a difference in temperature is called heat.

Metals conduct energy well, so the transfer continues along the spoon towards the handle. As its thermal energy increases, the handle becomes warmer. Stirring keeps bringing hot soup into contact with the spoon, although a metal spoon would also warm up if it were left standing in the bowl.

The handle usually warms more slowly because it is farther from the soup and loses some energy to the surrounding air. A wooden or plastic spoon does not warm as quickly because those materials do not conduct energy as well as metal.