After water is heated up, its thermal energy becomes kinetic energy. Kinetic energy is the energy of motion, and when water is heated, the energy of the heat causes the molecules in the water to move faster. This increase in movement results in an increase in kinetic energy.
Heat is a form of energy that is transmitted between two objects or systems that are at different temperatures. When heat is added to a substance, such as water, it increases the kinetic energy of the molecules in the substance, causing them to move faster and resulting in an increase in temperature. The thermal energy of the water is converted into kinetic energy as the molecules move faster and the water becomes hotter.
It is important to note that the transfer of heat between objects or systems is governed by the laws of thermodynamics, which dictate how energy can be transformed and exchanged.