B due to a moving point charge

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B due to a moving point charge
where ?0 4?x10-7 T.m/A
Biot-Savart law B due to a current element
B on the axis of a current loop
B inside a solenoid
B ?0 nI, where n
N/?
B due to an infinite long straight wire
Amperes Law Note Amperes law is valid only if
currents are continuous with a high degree of
symmetry
We used Amperes law to determine magnetic fields
for an infinite straight wire, a solenoid, and
inside and outside a wire.
Magnetic force on a current element
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Right-hand rule The magnetic lines of B curl
around a current- carrying wire in the same
direction as the fingers of the right-hand when
the thumb points in the direction of the current
as shown.
Magnetic lines due to a current in circular coil.
If you are standing to the left of the picture,
the current in the coil is clockwise
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In weber (Wb), 1Wb 1 T.m2
Magnetic flux
If a plane surface of area A and constant B with
an angle ? between directions of A and B
If there are N turns
Faradays Law
Lenzs Law The direction of the induced
current is such that the induced field is to
oppose the change in the original magnetic flux.
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Inductance
Self-inductance
Units of inductance
Henry (H) 1H 1 Wb/A 1 T.m2/A
Self-inductance of a solenoid
Mutual inductance
For example, the mutual inductance for The outer
solenoid is
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Magnetic energy stored in a inductor
Magnetic energy density
AC generator emf generated
rms current
AC in a resistor
AC in an inductor
AC in a capacitor
Inductive reactance XL ?L
Capacitive reactance XC 1/?C
Average power Dissipation