Describe a process in which energy changes forms at least twice. are there any unwanted forms of energy that are produced during the energy transformations?

Explanation:

Consider the example of the electric fan. The electrical energy used in the electric fan is greater than the kinetic energy of the moving fan blades.

According to the law of conservation of the energy, the energy is neither created nor destroyed. It always remains same.

The electrical energy used in the electric fan is also used in the producing unwanted sound energy.

The electrical energy in the electric fan is converted into any unwanted forms of energy. Like in producing unwanted sound energy and the heat energy. If the electric fan shakes then some of the electric energy is converted into unwanted kinetic energy.

Here, the electrical energy changes into sound energy, heat energy and kinetic energy.