Calculating Electrons for 4.00nC Negative Charge

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To determine the number of electrons needed for a negative charge of 4.00nC, the calculation involves dividing the charge by the elementary charge (1.602 x 10^-19 C). The correct calculation yields approximately 25 billion electrons, while the book states the answer is 390 billion, which is considered incorrect by forum participants. It is suggested that textbooks may have outdated or erroneous answers due to changes in problem editions. The consensus is to trust the calculation method rather than the book's answer.
Magna1
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THe question is.
How many electrons must be transferred to a body to give it a negative charge of 4.00nC.?/
So going with what I think 4*10^-9/1.602189...*10^-19=
=25*10^9.
BUT the answer in my book. is 390*10^-9.
What am I missing. Is this negative thing screwing me up or is the answer in my book wrong?
I Can't find anywhere in my book that helps.
 
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Your method and answer seem correct. The book's answer is silly. :smile:
 
OFten what happens: a book will change their problems slightly when a new edition is made, but sometimes they forget to change the selected answers in the back.
 
Thanks

Hopefuly that was it. Cause I went into my test today with the way I was doing it, Forget the book maybe I should just ask you guys.
Thanks
 
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