Electric Field and Forces Problem?

[AnnieF]

Homework Statement

A point charge of mass 0.210 kg, and net charge +0.340*10^-6C, hangs at rest at the end of an insulating string above a large sheet of charge. The horizontal sheet of uniform charge creates a uniform vertical electric field in the vicinity of the point charge. The tension in the string is measured to be 5.67 N. Calculate the magnitude and direction of the electric field due to the sheet of charge.

Homework Equations

E=F/q

F=Q1Q2K/r^2

The Attempt at a Solution

I am not entirely sure how to do this, but this is my guess..could someone tell me if I am doing this right?

Ft-mg-Fe=0
Fe=Ft-mg
Fc=3.612 N

E=F/q
E=3.612/.340E-6
E=10623529.4 N/C
I am not sure how to tell what direction it will be in

 

[Redbelly98]

The Attempt at a Solution

I am not entirely sure how to do this, but this is my guess..could someone tell me if I am doing this right?

Ft-mg-Fe=0
Fe=Ft-mg
Fc=3.612 N

E=F/q
E=3.612/.340E-6
E=10623529.4 N/C

Looks good.

I am not sure how to tell what direction it will be in

Can you tell what the direction of the electric force is?

 

[AnnieF]

Well I was thinking that it would have to be down, because the force of tension is greater than the force of gravity, so in order for the system to be not moving, the other force would have to pull downwards in order to cancel out the larger force of tension. Is this right?