854 10
C N
m
)
−
−
−
−
π
×
2
2
4
2
1
[15
(0 25) ] 10
m
−
+
×
×
=  3 99 × 106  N C–1 along QA Clearly, the components of these two forces with equal magnitudes
cancel along the direction OQ but add up along the direction parallel
to BA