A transformer having an efficiency of 90 % is working on 200 V , 3 kW power supply. If the current in the secondary coil is 6 A , then the voltage across the secondary coil and the current in the primary coil respectively, are

Question

A transformer having an efficiency of 90 % is working on 200 V , 3 kW power supply. If the current in the secondary coil is 6 A , then the voltage across the secondary coil and the current in the primary coil respectively, are (A) 300 V , 15A (B) 450 V , 15A (C) 450 V , 13.5A (D) 600 V , 15A

Tardigrade Admin · Accepted Answer

Power output =3kW× (90/100)=2.7kW Is=6A ∴ Vs=(2.7 kW/6 A)=450V ⇒ Ip=(3 kW/200 V)=15A

Q. A transformer having an efficiency of $90%$ is working on $200 V$ , $3 kW$ power supply. If the current in the secondary coil is $6 A$ , then the voltage across the secondary coil and the current in the primary coil respectively, are

$300 V$ , $15 A$

$450 V$ , $15 A$

$450 V$ , $13.5 A$

$600 V$ , $15 A$

Power output $= 3 kW \times \frac{90}{100} = 2.7 kW$
$I_{s} = 6 A$
$∴ V_{s} = \frac{2.7 kW}{6 A} = 450 V$
$\Rightarrow I_{p} = \frac{3 kW}{200 V} = 15 A$

Q. A transformer having an efficiency of 90% is working on 200V , 3kW power supply. If the current in the secondary coil is 6A , then the voltage across the secondary coil and the current in the primary coil respectively, are

300V , 15A

450V , 15A

450V , 13.5A

600V , 15A