Module 6 - 6.3.1 Magnetic Fields Flashcards
A Magnetic Field is
a region around a permanent magnet/a moving charge in which another body with magnetic properties feels a force
Magnetic Flux Lines show the
Shape and Direction of a Field
Flux Lines Point
North –> South
The closer the flux lines
the stronger the magnetic field
Magnetic Elements (3)
Cobalt, Iron, Nickel
Magnetic Flux Density (definition) (+ measured in)
F/IL where
- F = force acting on a wire
- I = current at 90 degrees to the magnetic field
- L = length of wire
measured in Teslas (T)
Use the Right Hand Grip Rule to …
determine the direction of the field around a current carrying wire
Shaping a wire into a coil
increases the strength of the magnetic field as the concentric flux lines around the wire add together
A solenoid is a
Long coil of current carrying wire
If the direction of the current is reversed
The direction of the field also reverses
Inside a solenoid the field is
strongest and very uniform
Outside a solenoid the field is
similar to that of a bar magnet
If an iron core is placed inside a solenoid
the magnetic field increases considerably
The Motor Effect
When the magnetic fields from a wire and a magnet interact the resultant field causes an upward force acting on the wire
The wire will experience the greatest force when it is
perpendicular to the magnetic field lines
Fleming’s Left Hand Rule
- thuMb = motion
- First finger = field (north → south)
- seCond finger = current (conventional)
