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Dramachick828
Jan 20, 2009, 05:52 PM
A professor pets her cat, which is initially neutral, as is she (even in an election year). Immediately afterwards, the professor reaches for a doorknob and feels a shock as electrons travel from the knob into her hand. Is the cat positively charged, negatively charged or electrically neutral?

I think the cat would be negatively charged, but... help? Thank you!

sarnian
Jan 20, 2009, 06:34 PM
... as electrons travel from the knob into her hand.
Are electrons charged positive or negative?
As electrons travel to her hand, what charge must her hand have?
And where did the charge of her hand come from?

Has that any consequence for the question "Is the cat positively charged, negatively charged or electrically neutral?"
So the answer to the question is??

Dramachick828
Jan 20, 2009, 06:40 PM
Electrons are charged negatively.
The question is very basic, I think the hand must have had the opposite of whatever the charge of the door was so that the door's particles would fly to her hand...
And so the particles in her hand would also be oppositely charged to the cat in order to pick them up...
It says the cat is initially neutral.
? I know, right? :D

sarnian
Jan 20, 2009, 08:14 PM
Electrons are charged negatively. Yes.

I think the hand must have had the opposite of whatever the charge of the door was so that the door's particles would fly to her hand... Yes and no.
The question stated that "electrons travel from the knob into her hand". What attracts electrons ? So was her hand charged negative or positive ?

Yes : it is basic : if some item goes by some action from neutral to negative, than that other item has to go from neutral to positive (or the other way around) !

And as both cat and prof were initial neutral, the charge of the hand came from... where ?
So the other item changed from neutral into..