Electron Suspended Between the Surface of The Earth

PepeF.
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Homework Statement



An Electron remains suspended between the Earth (assumed nueutral) and a fixed positive point charge, at a distance of 6.37 m from the point charge.
Determine the charge for this to happen.
answer must be in C.

Homework Equations


g= 9.8 m/s^2
Coulomb constant = 8/98755e9 N* m^2/C^2
Kc= 8.99e9
Fe= Kc (q1*q2)/r^2

The Attempt at a Solution



I am confused with this question,. please help me out
 
Last edited:
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What's the question asking for?
 
1Kris said:
What's the question asking for?

it says

determine the charge for this to happen
 
Well think in terms of force of the condition that causes this equilibrium. Write down the equation for the two forces involved and the rest is just simple algebra (then a calculation when you stick the numbers in).
 
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