A $12 V, 60 W$ lamp is connected to the secondary of a step down transformer, whose primary is connected to ac mains of $220 V$ . Assuming the transformer to be ideal, what is the current in the primary winding?

Option 1 -

$0.37 A$

Option 2 -

$0.27 A$

Option 3 -

$2.7 A$

Option 4 -

$3.7 A$

2 Views | Posted 3 weeks ago

Asked by Shiksha User

1 Answer

Answered by

Raj Pandey | Contributor-Level 9

3 weeks ago

Correct Option - 2

Detailed Solution:

For transformer $(\frac{i_{p}}{i_{s}}) = (\frac{V_{s}}{V_{P}}) = (\frac{N_{s}}{N_{P}})$

For bulb, $V s = 12 V$

$\begin{array}{r} i_{s} = (\frac{60}{12}) = 5 A \\ \Rightarrow \frac{i_{p}}{5} = (\frac{12}{220}) \\ i_{P} = \frac{60}{220} = (\frac{3}{11}) = 0.27 A \end{array}$

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A $12 V, 60 W$ lamp is connected to the secondary of a step down transformer, whose primary is connected to ac mains of $220 V$ . Assuming the transformer to be ideal, what is the current in the primary winding?

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A 12 V , 60 W lamp is connected to the secondary of a step down transformer, whose primary is connected to ac mains of 220 V . Assuming the transformer to be ideal, what is the current in the primary winding?

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A $12 V, 60 W$ lamp is connected to the secondary of a step down transformer, whose primary is connected to ac mains of $220 V$ . Assuming the transformer to be ideal, what is the current in the primary winding?