Frictional charging and weight of the body involved

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logearav
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Homework Statement



If a body is charged by rubbing it, its weight
a) may slightly increase of slightly decrease
b) increases slightly
c) decreases slightly
d) remains constant


Homework Equations





The Attempt at a Solution


I know weight is nothing but gravitational force exerted on the body and it acts vertically downward. If a body is charged by rubbing one is positive and other is negative. I also know weight varies from place to place since W = mg, and the value of g vary from place to place. So when charged by friction one has more protons(positive charged body) and other has less number of protons(negative charged body), so when used in the formula weight may changed. So i feel the answer is weight may slightly increase or slightly decrease, that is option (a). Am i correct?
 
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logearav said:
I know weight is nothing but gravitational force exerted on the body and it acts vertically downward. If a body is charged by rubbing one is positive and other is negative. I also know weight varies from place to place since W = mg,
Different objects may have different weights.
and the value of g vary from place to place.
true but not relevant to this problem since you are not changing where you are.
So when charged by friction one has more protons(positive charged body) and other has less number of protons(negative charged body),
It's the electrons that move - but otherwise your reasoning is sound
so when used in the formula weight may changed. So i feel the answer is weight may slightly increase or slightly decrease, that is option (a). Am i correct?
Basically you want to argue that electrons have weight, and electrons are removed to make a positively charged object and added to make a negatively charged object. Since the sign of the charge is unspecified...

As a policy I don't confirm the correctness or otherwise of your conclusions.
The idea is that you should realize the correctness yourself, by understanding the physics.
(In multi-choice there is a risk a student would just post the question 4 times - each with one answer and asking "is this right"? :) )