Consider three charges arranged as shown.(adsbygoogle = window.adsbygoogle || []).push({});

6.5 [tex]\mu C [/tex] 4.5 [tex]\mu C [/tex] -1.2 [tex]\mu C [/tex]

x--------3.9 cm----------x-----1.2 cm-------x

Sorry, I can't post the picture on here, but basically it's 3 charges in a row, seperated by 3.9 and 1.2 cm.

What is the electric field strength at a point 2.7 cm to the left of the middle charge Answer in units of N/C.

First I drew a diagram and figured out that the total E field would be to the right

The point would be located 1.2 cm to the right of the first charge, and 2.7 cm to the left of the second charge.

Then I used the equation for Electric Field, k*q/r^2

k*(6.5 x 10^-6)/ (.012)^2 - k*(4.5 x 10^-6)/(.027)^2 + k* (1.2x 10^-6)/ (.012)^2 .

where k= 9 x 10^9.

Plugging in and solving gave me 4.26 x 10^8 N/C, which isn't right... can someone please help me?

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Electric field problem

**Physics Forums | Science Articles, Homework Help, Discussion**