Finding Zero Net Electrostatic Force of +ve Charge b/w q1 & q2

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forty
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Two point-like objects carry charges of q1 = +4C and q2 = -3C and are separated by
a fixed distance of 50 cm.

(a) Determine the point (other than infinity) at which a point-like positive charge will
experience zero net electrostatic force due to the two fixed charges.

q1 = +4C ...... q2 = -3C ...... +ve charge
.. + <----------.5m----------> - <---------xm---------> +

+ve charge has to be closer to the q2 charge but further away from q1. ( positive charge = 1.6*10^-19 C )

So you need to balance forces?

let q = positive charge
Force q1 on q = -Force q2 on q
(4C * q)/(.5 + x)^2 = -(-3C * q)/x^2

Have I set this equation up properly?

Any help greatly appreciated,
Thanks!

EDIT: I figured out my problem. I wasn't using the quadratic formula properly to solve for x. So how do I delete a post?
 
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forty said:
Two point-like objects carry charges of q1 = +4C and q2 = -3C and are separated by
a fixed distance of 50 cm.

(a) Determine the point (other than infinity) at which a point-like positive charge will
experience zero net electrostatic force due to the two fixed charges.

q1 = +4C ...... q2 = -3C ...... +ve charge
.. + <----------.5m----------> - <---------xm---------> +

+ve charge has to be closer to the q2 charge but further away from q1. ( positive charge = 1.6*10^-19 C )

So you need to balance forces?

let q = positive charge
Force q1 on q = -Force q2 on q
(4C * q)/(.5 + x)^2 = -(-3C * q)/x^2

Have I set this equation up properly?

Any help greatly appreciated,
Thanks!
Looks good to me :approve: