In metals such as copper, silver and aluminum the electrons are not tightly bound to the atoms. They are called “free electrons”. When electric voltage is applied, an electric field within the metal triggers the movement of the electrons, making them shift from one end to another end of the conductor.

With all of this in mind, an electron in a stable atomic state does not move in the sense of a solid little ball zipping around in circles like how the planets orbit the sun, since the electron is spread out in a wave. Furthermore, an electron in a stable atomic state does not move in the sense of waving through space.

The “electrical pressure” due to the difference in voltage between the positive and negative terminals of a battery causes the charge (electrons) to move from the positive terminal to the negative terminal. Any path through which charges can move is called an electric circuit.

Electrons, which continuously move in wire, are called Electric Current. For solid conductors, electric current refers to directional negative-to-positive electrons from one atom to the next. Current is flow of electrons, but current and electron flow in the opposite direction.

The protons and electrons of an atom are attracted to each other. They both carry an electrical charge. The positive charge of the protons is equal to the negative charge of the electrons. Opposite charges attract each other.

Kinetic energy is the energy of motion. All moving objects have kinetic energy. When an object is in motion, it changes its position by moving in a direction: up, down, forward, or backward.

Here are some examples of everyday objects that use electrical energy.

• Washing machine.
• Dryer.
• Television.
• Cell phone.
• Laptop.
• Air conditioning system.
• Flashlight.
• Heating system.

Cell phones (and cell phone towers) use low-powered radiofrequency (RF) energy, a type of non-ionizing radiation. Non-ionizing radiation is not able to break the chemical bonds in your body.

This is a very small amount of power and is easily generated from kinetic motion. A cell phone will dissipate about a watt (5 watts to charge). It’s not practical to charge a cell phone with a movement directly out of a watch, you’d need roughly a million of these kinetic movements.

The sound waves are carried to a thin metal disk inside the phone, called a diaphragm, and are converted into electrical energy. The electrical energy travels over wires to another phone and is converted from electrical energy to sound waves again which can be heard by someone on the other end of the phone!

The different types of energy include thermal energy, radiant energy, chemical energy, nuclear energy, electrical energy, motion energy, sound energy, elastic energy and gravitational energy.

Many forms of energy exist, but they all fall into two basic categories:

• Potential energy.
• Kinetic energy.

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Energy, in physics, the capacity for doing work. It may exist in potential, kinetic, thermal, electrical, chemical, nuclear, or other various forms. There are, moreover, heat and work—i.e., energy in the process of transfer from one body to another.

Energy sources are categorized as renewable or non-renewable. A source of energy is considered renewable if it comes from natural sources or processes that are constantly replenished. Examples are solar (from the sun), wind, water, geothermal (from the earth) and biomass (from organic materials).

There are three methods of energy transfer that we need to learn: conduction, convection, and radiation.

• Conduction: Heat is thermal energy, and in solids it can be transferred by conduction.
• Convection: Fluids, that is both gases and liquids, can transfer heat energy by convection.
• Radiation:

When we talk about residential uses of energy, these are the most basic uses of energy. They include watching television, washing clothes, heating and lighting the home, taking a shower, working from home on your laptop or computer, running appliances and cooking.