Draw the diagram. alternate the charges. With some thinking, you can see this is the only solution.
The two adjacent corners have an attractive net force, equal, so the resultant is toward the center:
Force= k2(cos45)2u*2u/3^2= 1.41k*2u*2u/9
Now the replelling force frm across the square is k2u*2u/(3sqrt2)^2= .5k(2u2u/9)
so the net force of attraction is...
(1.41-.5)k2u2u/9 N
There are four charges, each with a magnitude of 2.0uC. Two are postive and two are negative. The charges are fixed to the corners of a 3.0m square, one to each corner, in such a way that the net force on any charge is directed toward the center of the square. Find the magnitude of the net electrostatic force on any one of these charges.
2 answers
find the resultant force on the charge at the center