Why do teaspoons get hot when you stir a cup of tea?

The heat from the tea is transferred to the teaspoon through conduction. Conduction is the transfer of heat energy between two objects in contact with each other. When you stir a cup of tea, the hot tea water comes into contact with the metal teaspoon, and the heat energy from the water is transferred to the metal. This causes the teaspoon to heat up.

The rate at which a teaspoon heats up depends on a few factors, including:

* The temperature of the tea water. The hotter the water, the faster the teaspoon will heat up.

* The amount of contact between the teaspoon and the water. The more contact there is, the faster the teaspoon will heat up.

* The thermal conductivity of the teaspoon. Different metals have different thermal conductivities, which means that they transfer heat at different rates. Metals with high thermal conductivities, such as copper, will heat up faster than metals with low thermal conductivities, such as plastic.

You can reduce the amount of heat that is transferred to the teaspoon by using a teaspoon made of a material with a low thermal conductivity, such as plastic or wood. You can also reduce the amount of contact between the teaspoon and the water by stirring the tea less frequently.