What energy is stored in an object when it is stretched or compressed?

When an object is stretched or compressed, it stores energy in the form of elastic potential energy. This type of energy is associated with the position and arrangement of the object, specifically how far it has been deformed from its original shape. Think of a rubber band; when you stretch it, the energy is stored within the material itself, ready to be released when the band returns to its original state.

In contrast, kinetic energy relates to the motion of an object, chemical energy is stored within the bonds of molecules and is released during chemical reactions, and thermal energy is associated with the temperature of an object and the vibrational motion of its particles. None of these types of energy directly relate to the act of stretching or compressing an object. Therefore, elastic potential energy is the most accurate description of the energy stored in an object due to deformation.