Question

The primary winding of a transformer has 100 turns and its secondary winding has 200 turns. The primary is connected to an ac supply of 120 V and the current flowing in it is 10 A. The voltage and the current in the secondary are

• A. 240 V, 5 A
• B. 340 V, 7 A
• C. 290 V, 8 A
• D. 300 V, 9 A

Answer 1

The correct option is A 240 V, 5 A

We know that,

$\frac{N_s}{N_p}=\frac{V_s}{V_p}\Rightarrow \frac{200}{100}=\frac{V_s}{120}\Rightarrow V_s=\frac{200\times 120}{100}=240V$

Also,

$\frac{V_s}{V_p}=\frac{i_p}{i_s}\Rightarrow \frac{240}{120}=\frac{10}{i_s}{i}_s=\frac{10\times 120}{240}=5A$

Thus $V_s=240V,i_s=5A$