Download Direction of Current Flow

Electromagnetism
 Electricity and magnetism were originally considered separate
phenomenon. Hans Christian Oersted was the first to demonstrate that
electric charges and magnetism were related.
Magnetic Field Around a straight Conductor

Charges moving through a
produce a
magnetic field with the conductor located at the centre
► First Right Hand Rule: grasp the conductor so that:
 thumb
______________
(remember conventional current)
 fingers
Magnetic Field Around a Coil or Solenoid
 the magnetic field of a conductor can be intensified by bending it into a
coil or
N
 the magnetic field of each loop in a solenoid adds together forming a
N pole at one end and a S pole at the other end.
► Second Right Hand Rule: grasp the solenoid so that:
 fingers
______________
(remember conventional current)
 thumb
 the direction of the magnetic field depends on:

the way the wire is coiled
 and the direction of current flow (remember conventional current)
S