Electric Potential

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Review 2
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Example1The following four charges are located
inside a submarine 5.00 µC, 9.00 µC, 27.0
µC, and 84.0 µC. a) Calculate the net electric
flux through the hull of the submarine. b) Is
the number of electric field lines leaving the
submarine greater than, equal to, or less than
the number entering it?
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Solution
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Example2Consider a long cylindrical charge
distribution of radius R with a uniform charge
density ?. Find the electric field at distance r
from the axis where r lt R.
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Solution
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Example3Two conducting spheres with diameters
of 0.400 m and 1.00 m are separated by a distance
that is large compared with the diameters. The
spheres are connected by a thin wire and are
charged to 7.00 µC. a) How is this total charge
shared between the spheres? (Ignore any charge on
the wire.) b) What is the potential of the
system of spheres when the reference potential is
taken to be V 0 at r 8?
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Solution
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Example4Determinea) the capacitance
andb) the maximum potential difference that can
be applied to a Teflon-filled parallel-plate
capacitor having a plate area of 1.75 cm2 and
plate separation of 0.040 0 mm.
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Solution
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Example5An electric current is given by the
expression I(t) 100 sin(120pt), where I is in
amperes and t is in seconds. What is the total
charge carried by the current from t 0 to t
(1/240) s?
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Solution
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Example6A conducting rod of length l moves
with velocity v parallel to a long wire carrying
a steady current I. The axis of the rod is
maintained perpendicular to the wire with the
near end a distance r away, as shown below. Find
the magnitude of the emf induced in the rod.
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Solution
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Example7Consider an LC circuit in which L
500 mH and C 0.100 µF. a) What is the
resonance frequency ?0? b) If a resistance of
1.00 kO is introduced into this circuit, what is
the frequency of the (damped) oscillations?
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Solution