What is Energy?

Energy is the ability to do work. Energy is expressed in units of Joules. (J)

What are the differences between Kinetic, Mechanical, and Potential Energy?

Kinetic Energy is the energy in which an object contains because of its particular motion. Kinetic Energy depends on mass and speed. Potential Energy is the energy that an object has because of the position, shape, condition of the object. Potential energy is stored. Mechanical Energy is the amount of work an object can do because of the object's kinetic and potential energies.

What are the similarities between Kinetic, Mechanical, and Potential Energy?

Kinetic, Mechanical, and Potential Energy are all similar because they are all energies of motion.

The stored Potential Energy of the bow and string allows them to do work on the arrow when the string is released.

When you swing a hammer you give it Kinetic Energy, which does work on the nail.

As a pin is juggled, its mechanical energy is the sum of its potential energy and its kinetic energy at any point.

Energy Conversion in a Pendulum

• At the highest point in its swing, the pendulum is at maximum Potential Energy.
• As the pendulum starts to swim downwards it loses potential energy and gains kinetic energy.
• As it reaches the bottom of its swing the pendulum is at maximum kinetic energy.
• As the pendulum goes back up it loses kinetic energy and gains back potential energy.
• The pendulum is back at its highest point, and has maximum potential energy.

Light Energy

Light Energy is produced by the vibrations of electrically charged particles. Light energy is a form of kinetic energy because the sound waves are in motion.

The sun provides a natural source of light, and this light energy travels to Earth.

Just like the sun the stars provide a natural source of light, and the light travels to planet Earth.

The energy use to cook food in a microwave is a form of light energy.

The chemical energy stored in batteries gets transformed into electrical energy through the wires. Then when the flashlight turns on this gets transformed into light energy.

Therefore as a result of this, the filament heats up and starts glowing, converting electrical energy to light energy.

Chemical Energy

Chemical Energy is the energy of a compound that changes as its atoms are rearranged. Chemical Energy is a form of potential energy because it depends on the position and arrangement of the atoms in a compound.

The chemical energy is released as the wood burns, and is converted into thermal energy. The burning wood then turns to ashes.

When propane gas is burned when cooking on a grill, the chemical energy stored in the bonds of propane molecules, and heat it released for cooking.

The chemical energy in food is released while the food is being digested. Molecules in our food are broken down into smaller pieces. As the bonds between these atoms break a chemical action will occur, and new compounds are created. The foods we eat give us chemical energy.

Continuing Chemical Energy

Gasoline is burned in a car engine. As the gas burns, small explosions release thermal energy which makes the pistons move, so the car can go.

The batteries in this flashlight use chemical energy by storing the bonds holding chemical compounds together.

Sound Energy

Sound Energy is energy produced by an object's vibrations. Sound Energy is kinetic energy because sound is the

movement of energy through the substances.

The alarm clock vibrates and bumps the sound waves next to it and those sound waves vibrate and bump the sound waves and so on until the sound reaches your ear.

When a person hits the drum the sound travels through the air, and allows us to hear the vibrations leaving the drum.