2.ENERGY TRANSFORMATIONS:
A battery constains chemical energy which is transformed into electrical energy.Then a lighbulb transforms the electrical current into luminous and thermal energy.

The chemical energy in our muscles can be transformed into mechanical energy in order to move objects,such as the sofa in the picture.

Chemical energy can be stored in fireworks.When fireworks explode,that chemical energy is converted into light,heat,dsound and mechanical energy.

Photovoltaic solar panels transform luminous energy from the sun into electrical energy.

Internal combustion engines transform the chemical energy of fossil fuels into thermal energy.Most of this thermal energy is transformed into motion,but some is lost as heat.Some energy is also lost as sound when certain parts of the motor hit each other and vibrate.

A kitchen mixer converts electrical energy into kinetic energy to turn the machine's axis.Some of this kinetic energy is passed to the liquid,which moves around.Some energy is also lost as heat.

In stars,the nuclear energy of atoms,such as hydrogen,is transformed into very intense luminous and thermal energy.