What is energy?

Energy is what makes everything happen. It is involved in every action that we make. It powers your muscles, runs your car, and lights your home. Without energy you could not ride a bike, watch television, or fly in an airplane.

Different types of energy Energy can’t be made, just changed from one type to another. Here are some of the main types.

Light is a form of energy that we can see. Most of the energy on Earth comes from the Sun as light

Heat energy is the energy of atoms or molecules vibrating. The hotter an object gets, the faster and more violently the atoms or molecules vibrate.

Nuclear energy     is stored in atoms. Nuclear energy is used to run power plants that  generate electricity.

Electromagnetic energy   is carried by X-rays, radio waves, and microwaves.

Curiosity quiz Look through the “What is energy?” pages and see if you can identify the picture clues below.

Gravitational energy      is the stored energy in an object that has been lifted but is not allowed to fall. Dams can turn gravitational energy into electrical energy.

Kinetic energy 

 is the energy a moving object has.  The faster a car moves, the more kinetic energy  it has.

Electrical energy    can travel easily through wires. It is the energy we use to power devices in our homes

It’s electric! If you flip a switch to make something work, it probably runs on electricity. Most of the energy we use every day is electric. 

What is electricity? This magical power source comes from electrons—tiny charged particles on the outside of atoms. They move from atom to atom creating electrical energy, and this energy travels on a circuit. 

Simple circuit A flashlight works using a simple electrical circuit. Batteries produce electricity, which flows around the circuit to power the bulb so it lights up. 

Electricity When we talk about electricity, we use the same words over and over again.

The power of magnets

Magnets create an invisible force known as magnetism that repels and attracts certain substances, like iron. Electricity and magnetism have a close relationship. 

Can you field the force? A magnetic field is the space around a magnet where its force can be felt. The force gets weaker as the field gets farther from the magnet. It is strongest at the two poles.

Magnetic Earth The Earth acts like a gigantic magnet. It has a magnetic north and south pole, although they aren’t in the same place as the geographical poles, but are very close. Over the Earth’s lifetime the magnetic poles have switched around a few times.