Flashcards
P3.7 B - Transformers
Flashcards do conjunto (5)
- 1What is changed about the magnet in transformers, compared to magnets in generators?It is replaced with an electromagnet
- 2How is electromagnetic induction used in a transformer?2 coils are wrapped around an iron core. Coil 1 is switched on, creating a magnetic field. This induces a current in coil 2, creating a magnetic field in the opposite direction. The 2 field oppose each other. Coil 1 is switched on and off, changing the direction of the current, creating an alternating voltage.
- 3How can we figure out the difference of voltage across the 2 coils?initial difference across coil 1/ difference across coil 2 = no. of turns in primary coil/ no. of turns in secondary coil
- 4What is the relationship between the difference in voltage and number of turns?If there are more turns on the secondary coil than the primary coil, the induced voltage across the secondary coil is bigger than the applied voltage.
- 5Why, in practice, are transformers never 100% efficient?The wires get warmer as the current passes through. The iron core gets warmer. Therefore energy is dissipated.
Informações
- Descrição
- GCSE Physics (P3 Electric circuits) FlashCards sobre P3.7 B - Transformers, criado por lily bevan em 30-03-2018.
- Criado por
- lily bevan
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