Forms of Energy: Kinetic, Potential, Chemical

• Energy is the ability to perform work.
• James Joule was a scientist born in 1818 who studied energy and energy conversions.

Types of Energy

• Potential energy is energy due to an object's position or shape, examples include a car at the top of a hill, a stretched spring or a drawn bow and arrow.
• Kinetic energy is the energy of motion and is also known as mechanical energy; walking, throwing a ball, and a moving car are examples.
• Chemical energy is stored in the chemical bonds of atoms and molecules; food, fuel like coal and oil, and batteries are examples.
• Sunlight is the most important source of Light energy on Earth and enables plants to grow through photosynthesis; examples include a light bulb and a TV screen.
• Heat energy may increase the temperature of an object and is given off by the sun, a fire, or an oven.
• Electrical energy is delivered by electrons, and wires can supply it to machines; examples include a power outlet and lightning.
• Sound energy is a form of kinetic energy created when objects vibrate, causing air and eardrums to vibrate, allowing us to hear.
• Nuclear energy is stored in the nucleus of an atom, and when the nucleus is altered, the atom can release this energy; nuclear bombs and power plants are examples.

Energy Conversions

• Measurement of the temperature of water at the top and bottom of a waterfall revealed that the water's potential energy converts to heat energy as it falls.
• The principle of conservation of energy states that energy cannot be created or destroyed, rather, it is converted from one form to another.
• Electricity in homes converts to energy such as kinetic energy in washing machines, sound and light in TVs, and heat in kettles.
• Energy dissipation is when energy converts to a less useful form.

Energy Efficiency

• Energy efficiency is shown when a bulb is supplied with 100 joules of electrical energy, but only 2 joules convert to light energy, with the remainder dissipating as heat energy.
• Sankey diagrams illustrate energy flow with electrical energy entering shown in and light energy exiting to the right, with heat energy represented by a downward arrow.
• An arrow's thickness on a Sankey diagram represents the amount of energy being used.
• The amount of energy entering a bulb equals the amount of energy leaving the bulb.
• Energy efficiency is displayed as a percentage on products from A-G, with grade A being the most efficient and grade G being the least efficient.

Sources of Energy can be broken into two categories

• A renewable energy source will never be used up are classified as renewable.
• Examples include wind, solar, hydroelectricity, biomass, wave, tidal, and geothermal energy.
• A non-renewable energy source will not be regenerated in our lifetime.
• Examples include fossil fuels and nuclear fission with the advantageof being easy to transport, storage, and are relatively cheap.
• Renewable sources produce no harmful waste products

Sustainable Energy Usage

• Sustainability constitutes using a resource without depleting it.
• When used sustainably, energy should not damage the environment, should be available for multiple future generations, and available at a reasonable cost..
• Actions to ensure sustainable energy usage include replacing burning fossil fuels with renewable energy sources, using energy-efficient appliances, and reducing energy wastage by energy conservation.

Calculating Energy Use

• Energy use is calculated using the formula Work = Force (in newtons) x Distance (in meters).

Explore various forms of energy including potential, kinetic, chemical, light, heat, electrical, and sound energy. Learn how each type manifests in everyday examples and their fundamental roles in different processes. Understand energy as the ability to perform work, with a nod to scientist James Joule.