Summary A level Physics - Magnetism

Magnetism

,23rd October 2023
and
Magneric fieldfeeStrength
magnenc Density
B
Symbol is
·




·
Unit =
Tesla (t) or NA'mY


Definition :



unit
magnetic flux density is the
force per unit current per
length
on a
current-carrying wire in a
magnetic field .



They Always :



- ⑳0 from Worth -s South
·
Represent
Have direction
a
stronger find the close
they
are

· =

Vectors /




·
compasses line up with
field lines
.



- A compass North points in same direction as


field Lines .




Electromagnets
·
Most common is a solenoid


coil is diametre
greater length
than

↓
creates a space of a



uniform gidl
.

To
Increase
strength :
·
Increase arrest
no
encrease
of coils

of magnetically soft'
Insert
· iron care

· Recrease diametre


Convential current
-s Direction
>
of
Positive
movement
of positive
charge
negative .
-

, 3D Representation

-Thinke
⑨ of a dot


coming ,
away
from you
.

out
of
the
Page
↓ Inno the
Page
perpendicular to
it



magnetic field
·
Applies no and current .




Permeability
of ability of
the
I the measure a

material to support the
formation
magnetic field
it
of
a within




Increasing electromagnet strength
:



-
soft :on care means :


High permeability
C



· Easier
for magnetic field to be set up in material
· 200 ,
000
of space/air
X




Force field
on a
current-carrying
wire in a
Magnetic
Field :
Uniform Magnetic
·

Magnetic flux density constant
· field lines parallel
field lines
evenly spaced
· .




Effect of increasing distance



magneric flux density reduced
.




Fe on avewcayina
a


-




·

Magnetic field and face are
Always perpendicular to each .
other