**Practice Problem on Electric Field for Point Charges**
Q1=+5 micro-C - o-------------o P2
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3cm | | |
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v | |
Q3=-1 micro-C - o-------------o Q4=+7 micro-C
|-----3cm-----|

3 charges are arranged on a rectangle as shown above.
What is the electric field at P_{2}?
Give the x and y components, the magnitude, and the direction.
Specify the electric field to three significant places
and the angle to the nearest integer.
Use the convention that right is 0 degrees, up is 90 degrees,
left is 180 degrees, and down is 270 degrees.

ANSWER = ( E_{x} = 4.64e+7 N/C, E_{y} = 6.64e+7 N/C, |E| = 8.10e+7 N/C, angle = 55 degrees )