Wool as thermal insulator

Principle

In this experiment, the students observe the cooling of hot water in two screw-top glasses. One of the glasses is covered with a felt jacket and the other is not. They find that felt insulation causes the water in this screw-top jar to cool more slowly.

In doing so, students learn about the concept of insulation and understand that by shielding a container from heat exchange with the environment, the temperature inside can be preserved longer.