St. Mary's H.S. Physics YouTube Channel




INduction - Charging w/o contact


Conduction and Induction - Flash
[ HTML5 ]
St. Mary's H.S.




[ Flash ]

No charge is transferred

Electrons redistributed




Case II - Induction w/ Negative Rod





Frame 1 - Neutral Electroscope



#p = #e-





Frame 2 - Rod comes near


Compare #p with #e-

[ Flash ]

#p = #e-


Electroscope is neutral


Knob (top) Positive

Leaves - negative


Frame 3
Rod Removed, Charges Return

Electroscope is neutral






Which diagram best represents the charge distribution on three neutral spheres when a positively charged rod is brought near sphere x, but does not touch it?

Jan. 2003 Regents



Choice 4

Electrons are attracted to rod







Why does a charged balloon stick to a wall?






"Which image

correctly shows the

electron distribution

of a negative balloon

touching a neutral wall?"


June 1996




Choice 3





Pith ball and negative rod

St. Mary's Physics YouTube Channel

School blocks YouTube? Use the file below.

Pith Ball And A Charged Rod.mp4





What charge(s)
could this ball have?






Negative or Neutral







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