Read About Faraday Cages in Wikipedia

A metal cage creates a shield against
very strong electric fields

University of Tehran High Voltage Lab. Person in cage: Prof. H.Mohseni

School blocks YouTube? Use the file below.






Faraday Cage Protects from 100,000 V

Physikshow of the University of Bonn




Here's how it works

Stanisław Skowron






3. Induction - Positive Rod


[ Flash ]


No charge is transferred

Electrons redistributed






Induction with a Positive Rod








Frame 1 - Neutral Electroscope


[ Flash ]

#p = #e-







Frame 2 - Rod comes near

[ Flash ]

Charge on electroscope?


#p = #e-

Electroscope is neutral


Charge of Knob (top)?




[ Flash ]

Charge of Leaves?








Frame 3 - Rod Removed,
 Charges Return


[ Flash ] 


Electroscope is neutral





"What would happen
 to the leaves of this electroscope if a
positively charged rod
were brought near the
top of the electroscope?"




"Electrons would be
attracted  up from leaves toward positive rod.
Leaves would become
more positive and
diverge more







"Which graphic shows

the electron distribution

of a neutral electroscope

near a positive rod?"





Choice 4

"Electrons are attracted up towards the positive  rod"









Like a Bird on a Wire

Electricity, Height and Women

Clip from Straight Up: Helicopters in Action from David Douglas on Vimeo.

Segment from the helicopter documentary "Straight Up!", showing power line
maintenance being performed on live wires by a man outside a helicopter, using a type of Faraday cage.




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