A 10 kVA 500/100 V transformer has the resistance referred to primary is 0.3 Ω. The equivalent resistance of transformer referred to secondary is:

Correct option is C

​$$\text{Given that,}$$

$$V_P = 500 \text{ V}, \quad V_S = 100 \text{ V}, \quad R'_1 = 0.3 \Omega$$

$$\text{So that equivalent resistance of transformer referred to the secondary side can be calculated as}$$​$$\frac{0.3}{R'_2} = \left(\frac{500}{100}\right)^2$$

$$\therefore R'_2 = 0.012 \Omega$$​​​​​