IGCSE Physics

Syllabus content4.5 Electromagnetic effects4.5 (a) Electromagnetic inductionCore• Describe an experiment that shows that a changingmagnetic field can induce an e.m.f. in a circuit4.5 (b) a.c. generatorCore• Describe a rotating-coil generator and the use of sliprings• Sketch a graph of voltage output against time for asimple a.c. generator4.5 (c) TransformerCore• Describe the construction of a basic iron-coredtransformer as used for voltage transformations• Recall and use the equation V p/V s= N p/N s• Describe the use of the transformer in high-voltagetransmission of electricity• Give the advantages of high-voltage transmission4.5 (d) The magnetic effect of a currentCore• Describe the pattern of the magnetic field due tocurrents in straight wires and in solenoids• Describe applications of the magnetic effect ofcurrent, including the action of a relay4.5 (e) Force on a current-carrying conductorCore• Describe an experiment to show that a force actson a current-carrying conductor in a magnetic field,including the effect of reversing:– the current– the direction of the fieldSupplement• State the factors affecting the magnitudeof an induced e.m.f.• Show understanding that the direction ofan induced e.m.f. opposes the changecausing itSupplement• Describe the principle of operation of atransformer• Recall and use the equationV pI p= V sI s(for 100% efficiency)• Explain why energy losses in cables arelower when the voltage is highSupplement• State the qualitative variation of thestrength of the magnetic field over salientparts of the pattern• Describe the effect on the magnetic fieldof changing the magnitude and direction ofthe currentSupplement• Describe an experiment to show thecorresponding force on beams of chargedparticles• State and use the relative directions offorce, field and currentCambridge IGCSE Physics 0625. Syllabus for examination in 2015.29