Chapter 25 CapacitanceII

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Chapter 25 Capacitance-II In the last lecture
we calculated the capacitance C of a system of
two isolated conductors. We also calculated the
capacitance for some simple geometries. In this
chapter we will cover the following
topics -Methods of connecting capacitors (in
series , in parallel).
-Equivalent capacitance.

-Energy stored in a capacitor.

-Behavior of an
insulator (a.k.a. dielectric) when placed in the
electric field created in the space between the
plates of a capacitor.
-Gauss law in the
presence of dielectrics.
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HITT
An electron moves from point i to point f, in the
direction of a uniform electric field. During
this displacement
j
i

• A. the work done by the field is positive and the
  potential energy of the electron-field system
  increases
• B. the work done by the field is negative and the
  potential energy of the electron-field system
  increases
• C. the work done by the field is positive and the
  potential energy of the electron-field system
  decreases
• D. the work done by the field is negative and the
  potential energy of the electron-field system
  decreases
• E. the work done by the field is positive and the
  potential energy of the electron-field system
  does not change

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HITT

• A parallel-plate capacitor has a plate area of
  0.2m2 and a plate separation of 0.1 mm. To obtain
  an electric field of 2.0 x 106 V/m between the
  plates, the magnitude of the charge on each plate
  should be
• A. 8.9 x 10-7 C B. 1.8 x 10-6 C C. 3.5 x
  10-6 C D. 7.1 x 10-6 C E. 1.4 x 10-5 C

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