# Electric field at origin due to 6 charges.

1. Feb 3, 2010

### MelodyE427

Problem: Charges are located in a gridline figure. The figure has these points: (-0.2m,0.3m) -2 microC, (-0.2m, 0m) +2 microC, (-0.2m,-0.3m) -2 microC, (0.2m,0.3m) +2 microC, (0.2m,0) +2 microC, and (0.2m, -0.3m) +2 microC.
a) Calculate x and y components of the electric field at the origin due to the six charges. (Try to make use of any symmetry that exists before you calculate)

Solution: I feel like the Ex component will be zero because of symmetry but am not completely sure about that because of the positive and negative charges that lie above and below the x axis. As far as the Ey component goes, i'm really unsure how to calculate it. I know to use the equation E=kq/r2 but don't really know where to start from.

2. Feb 4, 2010

### ehild

Draw a picture of the six charges and draw the vector of the electric field originating from each charge. Remember, the electric field of a point charge at the origin is parallel to the straight line connecting the charge with the origin, and points away from the charge if it is positive, and towards the charge when it is negative.

ehild