- #1
rms5643
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Homework Statement
What is the force F on the 1 nC charge at the bottom?
Figure: http://session.masteringphysics.com/problemAsset/1384340/5/pic1.jpg
Homework Equations
Coulomb's law - k*qq/r^2
The Attempt at a Solution
1) After splitting up the net force into their respective vectors, I assume that the X vectors from the two 2.0 nC charges cancel out. As a result, I believe this problem only involves computation of the Y direction.
2) -6 nC on the 1.0 nC:
8.99*10^-9 * (6.6*10^-9) * (1.0^-9) / (5*10^-2)^2
* Pulls upwards, thus positive force
3) 2.0 nc on the 1.0 nC (Y component):
(8.99*106-9 * (2.0*10^-9) * (1.0*10^-9) / (5.10^-2)^2 ) * cos(45) * 2 (<-- Since there are two 2.0 nC charges contributing to the net Y force)
* Pulls downwards, thus negative force
4) Net X = 0
Net Y = (8.99*10^-9 * (6.6*10^-9) * (1.0^-9) / (5*10^-2)^2) - ((8.99*106-9 * (2.0*10^-9) * (1.0*10^-9) / (5.10^-2)^2 ) * cos(45) * 2)
Net Y = -0.000029 (Rounded to two sig figs)
This answer is incorrect. Where did I go wrong?