Answer:
The magnitude of the electric force is [tex]F_e = 0.00098 \ N[/tex]
Explanation:
From the question we are told that
The mass of the paper is [tex]m= 100 mg = 100 *10^{-6} \ kg[/tex]
The position is [tex]d = 8.0\ mm = 0.008 \ m[/tex]
Generally the magnitude of the electric force at the point of equilibrium between the electric force and the gravitational force is mathematically represented as
[tex]F_e = F_g = mg[/tex]
Where [tex]F_g[/tex] is gravitational force
substituting values
[tex]F_e = 100 *10^{-6} * 9.8[/tex]
[tex]F_e = 0.00098 \ N[/tex]
Now generally the gravitational force acts downward (negative y axis ) hence the reason the electric force is same magnitude but opposite in direction (upward + y - axis )
