Question

a transformer has a primary voltage of 36 volts and a secondary voltage of 108 volts. if the primary windings have 98 turns, how many turns are in the secondary windings? (voltage and number of turns are directly proportional.)

Explanation:

Set up the direct proportion equation

$$ \frac{V_p}{V_s} = \frac{N_p}{N_s} $$

$$ V_p = 36,\quad V_s = 108,\quad N_p = 98 $$

Solve for the unknown number of turns

$$ \frac{36}{108} = \frac{98}{N_s} $$

$$ \frac{1}{3} = \frac{98}{N_s} $$

$$ N_s = 98 \times 3 = 294 $$

Answer:

294