Force Between Parallel Current Carrying Wires

1
Force Between Parallel Current Carrying Wires
2
Magnetic Field Along Axis of a Current Carrying
Loop
3
http//www.mathworks.com/matlabcentral/fx_files/86
73/1/loop_field.png
4
Helmholtz Coil

• Two sets of tightly packed loops (coils)
• Used to create controllable uniform magnetic
  fields
• If oriented correctly, the coils can effectively
  negate the Earths magnetic field and provide a
  zero mag field region.

Superposition of coils fields
5
(No Transcript)
6
Useful Equations for the magnitude of the
Magnetic Field around simple geometries
Center of Curvature of an Arc Segment
radians Center of a current carrying loop of
radius R R away from an infinitely long
straight line of current R away from a
semi-infinite straight line of current Along
the central axis of a current loop of radius R
7

• A wire with current i 3.0A is shown. Two
  semi-infinite straight sections, both tangent to
  the same circle, are connected to the circular
  arc that has a central angle ? and runs along the
  circumference of the circle. The connecting arc
  and the two straight sections all lie in the same
  plane.
• If at the center of curvature of the arc the
  magnetic field is zero, what must ? be?

8
Amperes Law

• Gausss Law provides easy calculation of electric
  fields around symmetric charge distributions
• Amperes Law provides easy calculation of
  magnetic fields around symmetric current
  distributions

9
Amperes Law

• Gausss Law is general for ANY charge
  distribution
• Amperes Law is general for ANY current
  distribution (assuming the currents are
  steadynot changing with time)

10
Amperes Law
11
(No Transcript)
12
Field Around a Long Straight Wire
13
Field Inside a Long Straight Wire Carrying a
Uniform Current i
14
Solenoid (coil of wire)
15
Use Amperes to Approximate Mag Field Within
Solenoid
Weak Field outside of coil (0T)
Strong Uniform Field within coil