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Course: Electromagnetism (Essentials) - Class 12th > Unit 12

Lesson 3: How transformers work?
Science
Electromagnetism (Essentials) - Class 12th
How wireless charging and transformers work?
How transformers work?
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Transformers

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Problem

A laboratory instrument requires a 3 A current to operate.
The primary coil of a transformer draws a 5 A current from the AC source, while the secondary coil with 3500 turns powers the instrument.
What is the number of turns, NP, in the primary coil?
NP=
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi