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bmarson123
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Homework Statement
Two point charges q1 = 2[itex]\mu[/itex]C and q2 = -2[itex]\mu[/itex]C are placed at r1 = (3,0,0) m and r2 = (0,0,4)m respectively
i) What is the force of q1 (in vector form)?
ii) What is the electric field at the origin?
iii) What is the electric dipole moment of this arrangement (in vector form)?
iv) What is the potential energy contained in this arrangement of charges?
Homework Equations
F =[ k q1q2 / (mod (r1-r2) )3 ] (r1 - r2)
ET = [itex]\sum[/itex] Ei
E = (mod qi) / 4[itex]\pi[/itex][itex]\epsilon[/itex] mod ri
p = qd
U =Qq / 4[itex]\pi\epsilon[/itex] mod (r2 - r1)
The Attempt at a Solution
i) F = k [ -4x10-9 / 53 (3,0,-4)
= 0.288 (3,0,-4) N
ii) E1 = 2x10-9 / 4[itex]\pi[/itex][itex]\epsilon[/itex]3
= 5.99454 i
E2 = 2x10-9 / 4[itex]\pi[/itex][itex]\epsilon[/itex]4
= 4.49590 k
ET = (6.0,0,4.5) N/C
iii) d = r2 - r1
= (-3,0,4)
p =2x10-9 (-3,0,4)
= (-6x10-9 , 0, 8x10-9) C.m
iv) U = -4x10-9 /4[itex]\pi[/itex][itex]\epsilon[/itex] 5 = 7.2 J
Basically, I just wanted to know if this is all right because it comes up on every single exam and I don't want to think it's right for it not to be!