Grounded, neutral objects gain or lose electrons by induction.


 
Case III - Negative rod/neutral object

 

 

 

 

Electrons are repelled down into the ground. Object becomes positive

 

 


 

 

Case IV -Positive rod / neutral object

 

 

Neutral object becomes negative as electrons are drawn up from the ground

 

 


 

Case V – Induction w/ grounded electroscope

Frame 1 - Rod comes near  

Electrons repelled down to leaves 

Total Charge?

 

 

Zero

 

No charge transferred

 

Frame 2 - Electroscope is grounded 

 

Frame 3 - Ground Removed,
Electroscope Maintains Charge
 

 

Electroscope Charge?

 

 

Positive

 

 

Electrons left Electroscope

 


 

What would the charge on the the electroscope be if a positive rod were used? 

 

Negative

 

 

 
Induction Summary

- Rod/+ Electroscope

+ Rod/- Electroscope

 

 


 

 

 
Conduction Summary

-Rod/-Electroscope

+Rod/+Electroscope