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In a transformer the number of primary turns is four times that of the secondary turns. Its primary is connected to an AC source of voltage V . Then

Options

  1. Acurrent through its secondary is about four times that of the current through its primary.
  2. Bvoltage across its secondary is about four times that of the voltage across its primary.
  3. Cvoltage across its secondary is about two times that of the voltage across the primary.
  4. Dvoltage across its secondary is about 1 2 2 times of the voltage across its primary.

Correct answer

A. current through its secondary is about four times that of the current through its primary.

Step-by-step solution

In a transformer the primary and secondary currents are related by I s = N p N s I p And the voltage are related by V s = N s N p V p Where subscripts p and s refer to the primary and secondary of the transformer. Here, V p = V , N p N s = 4 ∴ I s = 4 I p And V s = 1 4 V = V 4

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