Term
| Maxwell's equations are used to explain |
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Definition
electric and magnetic fields
aka electromagentic theory |
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Term
Write all 4 of Maxwell's equations
(in words) |
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Definition
1. Gauss Law:ΦE= EAcosθ
(relates electric flux to its source; the electric field,charge and the area.
2. an similar equation for magnetic flux except that magnetic field lines do not end (like electric field lines).
3. Faraday's law: an electric field is produced by a changing magentic field
4. Ampere's law: a magentic field is produced by an electric current OR BY A CHANGING ELECTRIC FIELD (proved by Maxwell) |
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Term
A current produced by a changing electric field is called a _____ current.
An ordinary current is called a ____ current. |
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Definition
1. displacement current (ID)
2. conduction current
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Term
| describe what an electromagnetic field is |
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Definition
electromagnetic waves is a wave of interchanging magentic and electric fields that can propagate and travel throughout space.
aka: if a changing magnetic field produces an electric field=
that electric field is changing=
this will in turn produce a magentic field |
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Term
| The magintudes of B & E decrease with ____ |
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Definition
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Term
| The energy carried by the electromagnetic wave is proportional to ____ and the intesity of the wave decreases with ______ |
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Definition
1. square of the amplitude (E2 or B2)
2. 1/r2 |
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Term
| Electric and magnetic fields at any point are (perpendicular/parallel )to each other and is ( perpendicular/parallel )to the direction of wave travel |
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Definition
| perpendicular for both blanks |
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Term
| t or f: when electromagnetic waves travel through an empty space, there are no charges for the electric field lines to start or stop on. |
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Definition
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Term
| true or false: magnetic lines always form closed loops. |
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Definition
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Term
| why can Electromagentic waves propragate in an empty space? |
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Definition
| b/c they are waves of fields (not of matter like water) |
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Term
| what gives rise to electromagentic waves? |
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Definition
| acclerating electrical charges |
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