How Many Electrons Constitute a Negative Charge of 160 NC?

AI Thread Summary
An object with a negative charge of 160 NC corresponds to an excess of approximately 10^12 electrons, calculated using the formula 160E-9C divided by the charge of a single electron (1.6E-19C). There was some confusion regarding the initial calculation, but the correct answer is indeed 10^12 electrons. Additionally, when a negatively charged insulator is brought near two uncharged metallic spheres in contact, the sphere on the right will acquire a positive charge upon separation. The discussion highlights the importance of understanding charge distribution and the effects of induction in conductive materials. Clarification on the setup's symmetry was also sought to better understand the charge distribution.
Kathi201
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1. If an object is determined to have a negative charge of 160 NC, you can conclude that the object has an excess of
a. 10^ 9 electrons
b. 10^10 electrons
c. 10^11 electrons
d. 10^12 electrons
e. 10^13 electrons


I came up with c. 10^11 electrons by taking 160E-9C/1.6E-19C = 10^11. I just used numbers that I found so I'm not sure if this is right and if it is I don't understand the reasoning as to why it is correct. Any help would be appreciated



I also have one more question.

If you bring a negatively charged insulator near two uncharged matallic spheres that are in contact and then separate the spheres, the sphere on the right will have
a. no net charge
b. a positive charge
c. a negative charge
d. either a positive or negative charge
e. none of the above
 
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Kathi201 said:
I came up with c. 10^11 electrons by taking 160E-9C/1.6E-19C = 10^11. I just used numbers that I found so I'm not sure if this is right and if it is I don't understand the reasoning as to why it is correct. Any help would be appreciated
A small careless mistake here. You should have 10x10^11 which is 10^12.

Kathi201 said:
If you bring a negatively charged insulator near two uncharged matallic spheres that are in contact and then separate the spheres, the sphere on the right will have
a. no net charge
b. a positive charge
c. a negative charge
d. either a positive or negative charge
e. none of the above
Is there a picture of this? The question asks for "the sphere on the right", and I'm assuming that the setup isn't symmetrical to begin with.
 
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