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2 marksElectromagnetic Induction

CAPE Physics Unit 2 · 2005 · Paper 1 · Question 3(c)(iii)

A flat coil of wire consists of 500 circular loops of radius 2.0 cm placed perpendicular to a uniform magnetic field of 0.15 T between the poles of an electromagnet.

State TWO reasons why transformers are NOT usually 100 per cent efficient.

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Other parts of this question

  1. 3(a)(i)State Faraday's law of electromagnetic induction.[1 mark]
  2. 3(a)(ii)State Lenz's Law.[1 mark]
  3. 3(b)Giving an example, explain how Lenz's law can be considered as an application of the law of conservation of energy.[2 marks]
  4. 3(c)(i)Calculate the magnetic flux through each turn of the coil.[2 marks]
  5. 3(c)(ii)If the electromagnet is turned off and it takes 0.20 s for the field to go down to zero, what would be the e.m.f. induced in the coil of wire?[2 marks]

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