Essential Questions: What is energy and what are its basic forms? What is heat energy and how is it measured? What makes heat?

Energy is the ability to do work.  Energy can cause motion or create change.  We use it to do things for us. It moves cars along the road and boats over the water. It bakes a cake in the oven and keeps ice frozen in the freezer. It plays our favorite songs on the radio and lights our homes. Energy is needed for our bodies to grow and it allows our minds to think.  The main source of energy on Earth is the Sun.  Energy from the Sun warms Earth, makes plants grow and the wind blow, and helps water through the water cycle.    

Energy is found in different forms including light, heat, chemical, and motion. There are many forms of energy, but they can all be put into two categories: potential and kinetic.  Potential can be described as stored energy.  It has the ability to change to kinetic energy, the energy of motion.  Kinetic is described as moving or working energy.  Potential energy also has to do with an object’s position or height.  Food, fossil fuels, and batteries contain potential energy in the form of stored chemical energy. 

Energy comes in different forms and can change from one form to another.  Some energy is given off as heat when it changes form.  When energy changes form, some heat is given off.  You can measure the change caused by heat energy.  People change energy into forms they can easily use, such as electricity.  Machines also can change forms of energy.  Energy is in everything. We use different forms of energy every day.   Moving objects have energy. 

Forms of Energy: 

Heat - This form of energy makes particles of matter move faster.  We feel this energy as heat.  It is also called thermal energy.  Thermal energy moves as heat from a warmer object to a cooler object.    Examples are a toaster, light bulb, clock radio, girl jumping rope, rubbing your hands together & the Sun. 

Light - We see the Sun’s energy in this form.  Plants make food with light energy.  We also change other forms of energy into light so we can see it.  Examples are a light bulb, clock radio, toaster & the Sun. 

Sound - Sound happens when matter moves back and forth very quickly, or vibrates.  Examples are musical instruments & a clock radio. 

Electrical - This energy can pass through wires.  This form of energy can change into forms that run appliances in our homes.  Examples are a toaster & a light bulb. 

Mechanical - This is the energy of moving objects or movement.  The moving parts in our machines and playground equipment have this form of energy.  It kinetic energy.  Examples are a toaster & a girl jumping rope.