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Science Department Scheme of Work
Unit of Study: Unit 9 – Magnets and electromagnetism
Time allocated:
Learning Objectives to be covered:
12 lessons
Candidates should be able to:
State the properties of magnets
Give an account of induced magnetism
Distinguish between ferrous and non-ferrous materials
Distinguish between the magnetic properties of iron and steel
Distinguish between the design and use of permanent magnets and electromagnets
State the factors affecting the magnitude of an induced emf
Show understanding that the direction of an induced emf opposes the change causing it
Describe a rotating-coil generator and the use of slip rings
Sketch a graph of voltage output against time for a simple ac generator
Describe the construction of a basic iron-cored transformer as used for voltage transformations
Recall and use the equation (Vp /Vs) = (Np /Ns)
Describe the use of the transformer in high- voltage transmission of electricity
Give the advantages of high-voltage transmission
Describe the principle of operation of a transformer
Recall and use the equation Vp Ip = Vs Is (for 100% effi ciency)
Explain why energy losses in cables are lower when the voltage is high
Describe the pattern of the magnetic field due to currents in straight wires and in solenoids
Describe applications of the magnetic effect of current, including the action of a relay
State the qualitative variation of the strength of the magnetic field over salient parts of the pattern
Describe the effect on the magnetic field of changing the magnitude and direction of the current
State and use the relative directions of force, field and current
State that a current-carrying coil in a magnetic field experiences a turning effect and that the effect is increased by increasing the
number of turns on the coil
Relate this turning effect to the action of an electric motor
Describe the effect of increasing the current on a dc motor
Important references/resources:
Experimental skills and investigations objectives:
Oxford Complete Physics for Cambridge
IGCSE (p. 201 - 228)
Describe methods of magnetisation and of demagnetisation
Describe an experiment to identify the pattern of field lines round a bar magnet
Describe an experiment that shows that a changing magnetic field can induce an emf in a circuit
Describe an experiment to show that a force acts on a current-carrying conductor in a magnetic field, including the effect of
reversing: the current and the direction of the field
Describe an experiment to show the corresponding force on beams of charged particles
Oxford Complete Physics for Cambridge
IGCSE Revision Guide (p.105 – 109, p. 131 139 )
Demonstration 9 from TRK
Practicals 9.1 – 9.3 from TRK
W/S 9 from TRK
Fleming’s rules W/S
Transformers W/S
Generic Homework Tasks (to be completed by ALL students):
1. Questions 1 – 9 (p.226 - 227)
2. Assessment 9 from TRK
Formative Assessment (takes place prior to the summative
assessment):
Summative Assessment:

1. Practical write up – Investigating the strength of
electromagnets. Focus on planning.
2. Assessmnent 9 from TRK
45 minute mixed style question paper (based on past
examination questions) completed at the end of the unit of
study with questions from P1, P2 and P3.