Energy transformations and energy transfers

• Energy is a property that must be transferred to an object to perform work on or heat up that object.
• Energy is measured in units of joules (J).
• Energy will often be described as part of an energy system.
• In physics, a system is defined as an object or group of objects that defines the system, in physics, is a way of narrowing the parameters to focus only on what is relevant to the situation being observed.
• A system could be as large as the whole Universe, or as small as an apple sitting on a table.
• When a system is in equilibrium, nothing changes, and so nothing happens.
• When there is a change to a system, energy is transferred.
• If an apple sits on a table, and that table is suddenly removed, the apple will fall.
• As the apple falls, energy is transferred.
• • Energy is stored in objects in different energy stores
• Moving objects have energy in their kinetic store
• Objects gain energy in their gravitational potential store when they are lifted above ground
• Objects have energy in their elastic potential store if they are stretched
• Objects with charge (Like electrons and protons) interacting with one another have energy in their electrostatic store
• Magnetic interacting with each other have energy in their magnetic store
• Objects with energy in their chemical store can reledse energy in chemical reactions
• Atomic nuclei release energy from their nuclear store during nuclear reactions
• All objects have energy in their thermal store, the hotter the object, the more energy it has in this store