→Subscribe for new videos every day! http://bit.ly/todayifoundoutsubscribe →Why Do Superheroes Wear Their Underwear on the Outside?: http://bit.ly/1Ow7J0K Never run out of things to say at the water cooler with TodayIFoundOut! Brand new videos 7 days a week! In this video: In this video, we look at why some devices have two prong plugs and others have three, as well as whether it's safe to use a three prong to two prong plug adapter. Want the text version?: http://www.todayifoundout.com/index.php/2016/01/devices-two-prong-plugs-others-three/ References: http://ccd.fnal.gov/fire/Electrial_Safety.pdf http://www.physicsclassroom.com/class/estatics/Lesson-2/Grounding-the-Removal-of-a-Charge http://www.dummies.com/how-to/content/alternating-current-in-electronics-hot-neutral-and.html http://www.wisegeek.org/what-is-a-chassis-ground.htm https://www.cia.gov/library/publications/resources/the-world-factbook/geos/ch.html https://www.cia.gov/library/publications/resources/the-world-factbook/geos/us.html https://www.youtube.com/watch?v=-n8CiU_6KqE http://c03.apogee.net/contentplayer/?coursetype=foe&utilityid=citizenselectric&id=4678 http://www.worldenergyoutlook.org/resources/energydevelopment/energyaccessdatabase/ http://www.safeelectricity.org/information-center/library-of-articles/55-home-safety/317-ground-fault-circuit-interrupters-gfcis http://www.physicsclassroom.com/class/estatics/Lesson-2/Grounding-the-Removal-of-a-Charge http://hyperphysics.phy-astr.gsu.edu/hbase/electric/hsehld2.html http://enlightenme.com/grounding-wire/ http://forum.allaboutcircuits.com/threads/what-is-the-difference-between-neutral-and-ground.14393/ http://electronics.howstuffworks.com/everyday-tech/question110.htm https://www.youtube.com/watch?v=k3OHzKz0qNc