This prank is very simple,inside iphone charger I connect 2 pcs lithium battery 3 volts,the battery is connected directly to usb power jack.Other electronics is removed from charger for security reasons.
This prank charger you can give to someone friend to get it how it works without plug to the power.
Visit my blog:http://macoprojects.blogspot.com
Subscribe to me:http://www.youtube.com/subscription_center?add_user=macobt
Add a Teacher Note to share how you incorporated it into your lesson.