A star connected resistive network with 20Ω in each phase is supplied with a three-phase ac source of 400 V. What is the total power consumed in the circuit?

Correct option is D

​$$\text{For a star-connected resistive three-phase load:} \\[8pt]\bullet \ \text{Line voltage:} \qquad V_L = 400 \text{ V} \\[6pt]\bullet \ \text{Phase voltage:} \qquad V_{ph} = \frac{V_L}{\sqrt{3}} = \frac{400}{\sqrt{3}} \text{ V} \\[6pt]\bullet \ \text{Resistance per phase:} \qquad R_{ph} = 20 \, \Omega \\[14pt]\textbf{Power Calculation} \\[8pt]\text{For a balanced resistive load:} \\[6pt]P = 3 \times \frac{V_{ph}^2}{R_{ph}} \\[12pt]\text{Substitute values:} \\[8pt]P = 3 \times \frac{(400/\sqrt{3})^2}{20} \\[10pt]P = 3 \times \frac{160000/3}{20} \\[10pt]P = \frac{160000}{20} = 8000 \text{ W}= 8 KW$$​​