less than the potential difference across Use of data to draw a conclusion. the primary coil. AFL open ended question. Students should be able to: Exam questions. Understand the structure of the transformer. Learning Outcomes Explain how a transformer works. All students must know: Understand the difference between a up transformer and a step-down transformer. How a transformer works Transformers only work with a.c. Use the transformer equation. How step-up and step-down transformers are used in the National Grid Activities Should know: Students plan to make a model transformer using C-cores and insulated wire. High voltage is used in the National Grid to Go over how a transformer works. reduce current and energy losses by heating Plan an investigation, based on the apparatus already used, to find out Could know: how the number of turns on the primary and secondary coils affect the Eddy currents in the core reduce the transformer output efficiency of transformers Exam question sheet. Resources Safety and Technicians’ Notes An experiment that shows the basic principle Ensure students are not exposed to of any transformer can be found at dangerous amounts of electricity. Nelson Thornes Physics page 258. Check CLEAPPS for further information. Nelson Thornes Physics CD-ROM Physics P3 3.3 Transformers animation. Lesson 4 Transformers – Assessment Opportunities Specification Reference P3.3.2 Use of data to draw a conclusion. The basic structure of a transformer AFL open ended question. An alternating current in the primary coil produces a changing magnetic field in the Learning Outcomes iron core and hence in the secondary coil. This induces an alternating potential All students must know: difference across the ends of the secondary coil. Knowledge of laminations How a transformer works and eddy currents in the core are not Transformers only work with a.c. required. How step-up and step-down transformers are In a step-up transformer the potential used in the National Grid difference across the secondary coil is greater than the potential difference know: Should across the primary coil. In a step-down transformer the potential High voltage is used in the National Grid to difference across the secondary coil is reduce current and energy losses by heating
Use of data to draw a conclusion. AFL open ended question. Exam questions. Learning Outcomes All students must know: How a transformer works Transformers only work with a.c. How step-up and step-down transformers are used in the National Grid Should know: High voltage is used in the National Grid to reduce current and energy losses by heating Could know: Eddy currents in the core reduce the efficiency of transformers Safety and Technicians’ Notes Ensure students are not exposed to dangerous amounts of electricity. Check CLEAPPS for further information. Lesson 4 – Transformers Specification Reference P3.3.2 The basic structure of a transformer An alternating current in the primary coil produces a changing magnetic field in the iron core and hence in the secondary coil. This induces an alternating potential difference across the ends of the secondary coil. Knowledge of laminations and eddy currents in the core are not required. In a step-up transformer the potential difference across the secondary coil is greater than the potential difference across the primary coil. In a step-down transformer the potential difference across the secondary coil is less than the potential difference across the primary coil. Students should be able to: Understand the structure of the transformer. Explain how a transformer works. Understand the difference between a transformer and a step-down transformer. Use the transformer equation. Activities Students plan to make a model transformer using C-cores and insulated wire. Go over how a transformer works. Plan an investigation, based on the apparatus already used, to find out how the number of turns on the primary and secondary coils affect the transformer output Exam question sheet. Resources An experiment that shows the basic principle of any transformer can be found at Nelson Thornes Physics page 258. Nelson Thornes Physics CD-ROM Physics P3 3.3 Transformers animation. Assessment Opportunities Use of data to draw a conclusion. AFL open ended question. Learning Outcomes All students must know: How a transformer works Transformers only work with a.c. How step-up and step-down transformers are used in the National Grid Should know: High voltage is used in the National Grid to reduce current and energy losses by heating up
2731-AQA%20Physics%20P3.3%20SoW%20Keeping%20things%20moving%20SLCSE%20TB.docx