Electromagnetic

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Electromagnetic Discontinuities Must Propagate
at a speed
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(No Transcript)
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Our wavefront satisfies both Gausss
laws because there is no enclosed charge or
current, and fields on opposite sides of the box
are the same.
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There is a changing B flux as the wavefront moves
by. This changing flux must be equal to the line
integral of the E field. Only the back edge (gh)
contributes to this line integral.
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There is a changing E flux also. This gives
another reqd relation between E and B.
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Accelerating Charges Radiatehttp//www.its.calte
ch.edu/phys1/java/phys1/MovingCharge/MovingCharge
.html
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Accelerating Charges Radiate
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Coulombs law cant describe the kinked E
field. We got it from connecting field lines
geometry. However, we do get the kinked field if
we consider the potential.Potential
depends only on where the charge was and how
fast it was moving a time r/c ago. (In other
words, we have to account for the light travel
time.)(we will need to do better than just the
scalar electric potential, though)
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But whats it good for?

• http//www.youtube.com/watch?vQil3iFpgWdM

Demos
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Quiz What are you doing this summer (3 pts for
any answer)

• A Maybe a physics problem a week or so, just to
  stay in top mental condition
• B I wont pick up a physics book
• C I will use my expertise from Physics 161 to
  re-animate dead tissue.