Question

The voltage in the primary and the secondary coils of a step up transformer are 200 V and 4 KV respectively. If the current in the primary is 1 ampere then the current in the secondary coil will be

• A. 50 m A
• B. 500 m A
• C. 5 A
• D. 5 m A

Answer 1

Answer: (A)

50 m A

Power in transformer remains constant ,$P=VI$

$V\propto 1/I$

$\frac{V_P}{V_S}=\frac{I_S}{I_P}$

$\frac{200}{4000}=\frac{I}{1}$

$I=0.05=50mA$