Chapter 23: Electric Fields

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Chapter 23 Electric Fields

• The coulomb or electric force
  
• The electric field vector

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Example Problem 23.11

• Review problem. In the Bohr theory of the
  hydrogen atom, an electron moves in a circular
  orbit about a proton, where the radius of the
  orbit is 0.529x10-10 m. (a) Find the electric
  force between the two. (b) If this causes the
  centripetal acceleration of the electron, what is
  the speed of the electron?

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Example Problem 23.13

• What are the magnitude and direction of the
  electric field that will balance the weight of
  (a) an electron and (b) a proton?

Example Problem 23.22

• For the electric dipole, show that the electric
  field at a distant point on the x axis is

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Example Problem 23.17

• Three point charges are at the corners of an
  equilateral triangle as shown. Calculate the
  electric field at the position of the 2.00 ?C
  charge due to the other two charges.

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Electric Field Lines

• Field lines of a positive point charge

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• Two point charges

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Continuous Charge Distributions
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Example Problem 23.35

• A thin rod of length l and uniform linear charge
  density ? lies along the x axis. (a) Show that
  the electric field a distance y from the rod
  along its perpendicular bisector, has no x
  component and is given by E2ke?sin?0/y. (b)
  Using this result show that the field of a rod of
  infinite length is E2ke?/y.

?0