How many electrons have been removed from a positively charged electroscope?

AI Thread Summary
To determine how many electrons have been removed from a positively charged electroscope with a net charge of 7.5x10^-11 C, one must divide the net charge by the charge of a single electron, which is 1.6x10^-19 C. This calculation leads to the conclusion that the number of electrons removed is approximately 4.69x10^8. The participants confirm that this method is correct and express understanding of the calculation process. The discussion effectively clarifies the relationship between charge and the number of electrons.
mimictt
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Hello everyone! I'm having a problem with this question from my book...

How many electrons have been removed from a positively charged electroscope if it has a net charge o 7.5x10^-11 C?

Can someone explain to me how to solve this problem>?
Thank you very much!
 
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Hello,

What is the charge of a single electron? What about two? What about an arbitrary number call it "x" electrons?
 


What's the charge on each electron?
 


it's 1.6x10^-19 C

so does it mean that 7.5x10^-11/ 1.6x10^-19 is the number of electrons?
 


oh i think i got it! thank you so much!
 


mimictt said:
it's 1.6x10^-19 C

so does it mean that 7.5x10^-11/ 1.6x10^-19 is the number of electrons?

yes!
 
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