The document discusses electromagnetism and electromagnets. It defines an electromagnet as a temporary magnet created by winding wire into a coil around an iron core, which produces a magnetic field when current passes through. It outlines learning objectives about drawing magnetic field patterns, conducting experiments to study factors affecting magnetic field strength, and describing applications of electromagnets. Examples of applications mentioned are electric bells, circuit breakers, and loudspeakers.

1. 1
3.1
The
magnetic
effect of
current-
carrying
conductor
3.2
The force on
a current –
carrying
conductor in
a magnetic field
3.3
Electromagnetic
induction
3.4
Transforme
r
3.5
The generation
and transmission
of electricity
ElectromagnetismElectromagnetism

2. 22
ElectromagnetismElectromagnetism
3.13.1
AnalysingAnalysing the magnetic effect ofthe magnetic effect of
current- carrying conductorcurrent- carrying conductor

3. 3
Learning OutcomesLearning Outcomes
► A student is able to:A student is able to:
► State what an electromagnet isState what an electromagnet is
► Draw the magnetic field pattern due to a currentDraw the magnetic field pattern due to a current
in a :in a :
i.i. Straight wireStraight wire
ii.ii. CoilCoil
iii.iii. SolenoidSolenoid
► Plan conduct experiment to study factors thatPlan conduct experiment to study factors that
effect the strength to the magnetic field of aneffect the strength to the magnetic field of an
electromagnet.electromagnet.
► Describe and application of electromagnetDescribe and application of electromagnet

4. 4
ElectromagnetElectromagnet
►A temporary magnetA temporary magnet
made by winding a coil of insulatedmade by winding a coil of insulated
wire round a soft iron core,wire round a soft iron core,
so that a magnetic field is producedso that a magnetic field is produced
when a current is passed through thewhen a current is passed through the
coil.coil.

5. 5
The magnetic field patternThe magnetic field pattern
due to a currentdue to a current

6. 6
Experiment to study factors that effect the strength toExperiment to study factors that effect the strength to
the magnetic field of an electromagnet.the magnetic field of an electromagnet.

7. 7
Application of electromagnetApplication of electromagnet
Electric bell

8. 8

9. 9
Output circuit
Spring
brass
Spring
contac
t

10. 10

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Circuit breaker: An automatic switch which cuts off the
current in a circuit if this rises above specifiedvalue
1. High
current
flows
through
2. The magnetic field in
he coil becomes strong
5. No current flows after
the contact opened
current
6. Pressing the
reset button
closes the
contact again.
The opened
circuit will be
colsed
3. The electromagnet pulls
the iron catch out position
4. The contacts open and the circuit breaks

12. 12

13. 13
Loudspeaker
2. The overlapping
field of the coil
and magnet
create varying
forces on the coil.
1. Signal are fed
into the coil as
varying currents.
3. This causes the
paper cone to
vibrate and create
sound waves.

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