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Name:
Unid:
Final Exam
Discussion TA:
Show all
work!! Report all numbers to three (3) sisnificant fisures.
Two identical conducting small spheres are placed with their centers 0.300 m apart. One is given a charge of 12.0 nC and
the other a charge of -18.0 nC.
(a)
(b)
(c)
(d)
fiO pts.J Find the electric force exerted by one sphere on the other (treat each sphere as a point charge). Is this
force atfractive or repulsive?
[10 pts.J The spheres are then connected by a conducting wire. Find the electric force each exerts on the other
after they have come to equilibrium. Is this force attractive or repulsive?
fiO p*.J Find the electric potential energy of the two spheres before and after they are connected by the
conducting wire.
[10 pts.J Find the outward electric flux through a large surface surrounding the two spheres before and after the
spheres are connected by the conducting wire.
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Name:
Unid:
Final Exam
Discussion TA:
Show all
work!! Report all numbers to three
(3) sisnificant fieures.
Three equal positive charges q are at the corners of an equilateral triangle of side a as shown in
the figure.
(a)
(b)
fiO pts.J Sketch the electric field lines in the plane of the charges.
p0 pts.l Find the location of one point (other than infinity) where the electric field is
zero.
to tne two .4!
(c)
fi 0 pts.J What are the magnitude
(d)
fiO pts.J What is the electric potential at P due to the two charges at the base?
and direction of the electric field at P due
charges at the base?
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