Lesson 2 How is light produced?

What light is VS. What light isn’t Light is bright rays. Light isn’t dark. Light is a type of matter, something like plasma. Light isn’t solid. Light is streams of invisible, tiny particles, like radiation. Light isn’t made up of matter because we can’t feel it. Light is a beam of energy.

Luminous means these objects can produce or give out their own light Sources of Light LUMINOUS REFLECTED Lightbulb Mirrors Fire Road signs Lightning Movie screen Glow sticks Moon Luminous means these objects can produce or give out their own light

Energy Energy is the capacity to do work Work is done when a force moves an object Light is a form of energy – electromagnetic energy The Law of Conservation of Energy – energy cannot be created or destroyed, it can only change from one form to another

Forms of Energy Electromagnetic (Light) Electrical Thermal (heat) Mechanical Nuclear Chemical energy Gravitational energy

Potential Energy Potential = Stored energy Gravitational energy – energy an object has because of its position; anything “up high” Chemical energy – energy stored in a substance Fuel Batteries Food Nuclear energy – energy stored in the nucleus of an atom Sun

Kinetic Energy Kinetic energy = energy in motion Mechanical (motion) energy – movement of objects of substances from one place to another Electrical energy – electricity moving through an object Electromagnetic – energy that travels in waves Light Thermal (heat) energy – vibration of atoms to make heat Friction

Energy Transformations Example 1: Toaster plugged into an outlet Electrical  Thermal Example 2: Plugging a fan into an outlet _______________  _________________ and _______________ Example 3: Wind turbine to light

Now that we’ve practiced… What energy transformations took place in the flashlight and the candle? Flashlight: Candle: