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ACHE
THREE CHARGES ARE AT THE corners of equilateral triangle.calculate electric feild at left corner charge?
How would you actually do this? Well, define E2 to be on the x-axis, so \[E_{2(x)}=E_2\]\[E_{2(y)}=0\] And\[E_{1(x)}=E_1\cos(60)\]\[E_{1(y)}=E_1\sin(60)\]Add the x and y components
\[E=\frac{F}{q}=\frac{Qk}{r^2}\]
http://www.youtube.com/watch?v=OsWDUqJQcpk Watch the first 9 minutes, he explains something very similar to your problem on the 7th-9th minutes.
theree charges are at the corners of an equilateral triangle as shown in fig below , calculte the electric feild at the position of tha 2.00 micro colum charge due to the 7.00 micro columb and -4.00 micro columb charges.(b) use ur answer to detrmine the force on the 2.00 m|dw:1349627210442:dw|icro columb chare.
|dw:1349627494021:dw| Are you fine this far?
+ve direction=right E1x=\[\frac{-4* (9*10^9)}{r^2}\] E2x=\[\frac{7* (9*10^9)}{r^2} cos(60)\] E2y=\[\frac{7* (9*10^9)}{r^2} sin(60)\]
\[E=F/q\]Multiply by the charge Sorry! In my earlier calculations it should have been MICRO coulombs- multiply each by 10^-6!
*Multiply E field by the charge to get force