Question

On which of the following factor/s does the turns ratio of transformers depend?

• A. V_p and V_s
• B. V_p only
• C. V_s only
• D. I_p only

Answer 1

The correct option is A

V_p and V_s

To determine turn ratio for a transformer we need primary volatge, secondary voltage or primary current and secondary current. We use,
$\frac{N_p}{N_s}=\frac{V_p}{V_s}$

This shows that, for a turn ratio we use direct proportion. When we have to use currents in primary and secondary we use inverse proportion.
$\frac{N_p}{N_s}=\frac{I_s}{I_p}$