**Practice Problem on Electrical Force for Point Charges**
Q1=+5 micro-C - o-------------o Q2=-1 micro-C
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4cm | | |
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Q3=+4 micro-C - o-------------o Q4=-7 micro-C
|-----3cm-----|

4 charges are arranged on a rectangle as shown above.
What is the force on charge Q_{2}?
Give the x and y components, the magnitude, and the direction.
Specify the force 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 = ( F_{x} = -5.86e+1 N, F_{y} = 2.78e+1 N, |F| = 6.48e+1 N, angle = 155 degrees )