Question 322: AC fundamentals

Question

A transformer has 120 turns in the primary coil and carries 5 A current. Input power is one kilowatt. To have 560 V output, the number of turns in secondary coil will be

Accepted Answer

To find the number of turns in the secondary coil of a transformer, use the formula for the voltage ratio in a transformer:
$$ \frac{V_s}{V_p} = \frac{N_s}{N_p} $$
where:
$ V_s $ is the secondary voltage,
$ V_p $ is the primary voltage,
$ N_s $ is the number of turns in the secondary coil,
$ N_p $ is the number of turns in the primary coil.
Given:
$ V_s = 560 \, 	ext{V} $
$ N_p = 120 $ turns
The primary voltage $ V_p $ can be found using the power formula:
$$ P = V_p \cdot I_p $$
where:
$ P = 1000 \, 	ext{W} $ (1 kilowatt is the input power)
$ I_p = 5 \, 	ext{A} $ (current in the primary coil)
Solving for $ V_p $:
$$ V_p = \frac{P}{I_p} = \frac{1000 \, 	ext{W}}{5 \, 	ext{A}} = 200 \, 	ext{V} $$
Now use the voltage ratio formula:
$$ \frac{560 \, 	ext{V}}{200 \, 	ext{V}} = \frac{N_s}{120} $$
Solving for $ N_s $:
$$ N_s = \frac{560}{200} \cdot 120 = 2.8 \cdot 120 = 336 $$
Therefore, the number of turns in the secondary coil will be
336
.
Option C: 336

Answer

168

Answer

200

Answer

336

Answer

400

AC fundamentals

A transformer has 120 turns in the primary coil and carries 5 A current. Input power is one kilowatt. To have 560 V output, the number of turns in secondary coil will be

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