11 Natural Light Natural light is really important to humans But we can’t control themWe can’t turn the Sun on and off when we want toSome of the animals that we saw before use bioluminescence to survive (communication, attract food)
12 Artificial Light A long time ago, humans only had natural light How would their lives be different?
13 Artificial Light: Fire Humans learned how to control natural light sourcesThey found out how to make fire!They used fire to keep warm, cook with and also do things after the Sun went down
14 FirePeople learned they could burn other things than wood to make lightExamples?Wax – CandlesOil – LampsChemicals - Sparklers
15 Artificial Light Artificial: Made by humans Artificial Light: Light made by humansMost are made by electricityThis is another type of energyArtificial light is easy to control because they can be turned on and off with a switch
16 Bouncing Light? We talked about sunlight bouncing off the moon Artificial light bounces too!The reason we see road signs is because light from the car or streetlights bounces off the sign!
17 $ The Costs $ Natural Light is always free! Artificial Light always costs money!Buying lamps, electricity, oil, batteries, flashlightsEven candles, sparklers and reflective clothingWe should conserve money and energy by shutting off artificial lights when we can!OPEN A WINDOW!