What is the net charge of a metal sphere after adding 7.0 x 10^13 electrons?

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The discussion centers on calculating the net charge of a metal sphere initially charged at +5.0 µC after adding 7.0 x 10^13 electrons. Each electron has a charge of approximately -1.6022 x 10^-19 C, leading to a total charge of about -11.22 µC from the electrons. When this negative charge is added to the sphere's initial positive charge, the correct net charge is approximately -6.22 µC. Participants emphasize the importance of accounting for the negative charge of the electrons in the calculation. The conversation highlights the need for careful unit management and understanding charge polarity.
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A metal sphere has a charge of +5.0 µC. What is the net charge after 7.0 x 10^13 electrons have been placed on it?

What I tried was to convert the number of electrons to a charge by multiplying it by (1.6 x 10^-19)..and then adding that to the 5..from which I got 16.2..am I takin the right approach?
 
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The metal sphere has a +5 µC charge, which means a deficit of electrons.

Add to this 7.0 x 1013 electrons, each of which has a charge of -1.6022 x 10-19 C.

So the total charge of electrons is 7.0 x 1013 * -1.6022 x 10-19. Note that the electron charge is negative.
 
I'm not sure how you got 16.2. Did you take into account the charge of electrons (-)? Also, make sure to check the units of the metal sphere.

Aw, astronuc, beat me to it :wink:
 
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Ahh..I completely forgot the negative..thanks astronuc
 

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