Energy - the ability to cause change
There are many forms of energy, but five main forms of energy are: ◦ Heat/Thermal Part 1: Types of Energy ◦ Chemical ◦ Electromagnetic ◦ Nuclear ◦ Mechanical
The internal motion of atoms is called heat Chemical Energy is required to bond atoms energy, because moving particles produce together. heat.
When bonds are broken, energy is released. Heat/Thermal energy can be produced by
friction. Fuel and food are forms of stored chemical energy. Heat/Thermal energy causes changes in temperature and phase of any form of matter.
Power lines carry electromagnetic energy into The nucleus of an atom is the source of your home in the form of electricity. nuclear energy. When the nucleus splits (fission), nuclear energy is released in the form of heat energy Light is a form of electromagnetic energy. and light energy. Nuclear energy is also released when nuclei Each color of light (ROY G BIV) represents a collide at high speeds and join (fusion). different amount of electromagnetic energy. The sun’s energy is produced from a nuclear fusion reaction in which hydrogen nuclei fuse to form helium nuclei. Nuclear energy is the Electromagnetic Energy is also carried by X- most concentrated form of energy. rays, radio waves, and laser light. When work is done to an object, it acquires The main form of energy we will focus on in energy. The energy it acquires is known as this unit is Mechanical Energy. mechanical energy.
There are two types of mechanical energy: When you kick a football, you give mechanical Kinetic Energy and Potential Energy. energy to the football to make it move. ◦ Kinetic Energy is the energy of motion. ◦ Potential Energy is stored energy. When you throw a balling ball, you give it energy. When that bowling ball hits the pins, some of the energy is transferred to the pins (transfer of momentum).
The energy of motion is called kinetic energy. Potential Energy is stored energy that an object has because of its position.
The faster an object moves, the more kinetic energy it has. Potential Energy can be stored chemically in fuel, the nucleus of atom, and in foods, or
The greater the mass of a moving object, the stored because of the work done on it: more kinetic energy it has. ◦ Stretching a rubber band. ◦ Winding a watch. ◦ Pulling back on a bow’s arrow. Kinetic energy depends on the mass and ◦ Lifting a brick high in the air. velocity of an object.
There are two types of Potential Energy: Gravitational Potential Energy depends on
◦ Gravitational Potential Energy (Eg) height from a zero level ◦ Elastic Potential Energy (Es) This zero level is relative (it is where you place it)
The stored energy can be released by allowing the object to fall Elastic Potential Energy depends on the distance an elastic object (spring or rubber band) is compressed or stretched.
The length of an object when no external forces are acting on it is called the "relaxed length" of the object. This is the zero point.
No matter what type of energy a system has, the unit for energy is a Joule (J).