Posted: February 12, 2016
https://phet.colorado.edu/sims/html/balloons-and-static-electricity/latest/balloons-and-static-electricity_en.html
https://www.classzone.com/books/ml_science_share/vis_sim/emm05_pg7_charge/emm05_pg7_charge.swf
http://www.bbc.co.uk/schools/gcsebitesize/science/add_aqa/electricity/staticelecact.shtml
https://phet.colorado.edu/sims/html/john-travoltage/latest/john-travoltage_en.html
https://vimeo.com/57637498
