Question

A current of $5A$ is flowing at $220V$ in the primary coil of a transformer. If the voltage produced in the secondary coil is $2200V$ and $50$% of power is lost, then the current in the secondary will be

• A. $2.5A$
  
• B. $0.5A$
  
• C. $0.25A$
  
• D. $5A$
  

Answer 1

The correct option is C $0.25A$

Current on primary (input) coil $I_p=5A$

Voltage in primary coil $V_p=220V$

Voltage in secondary coil $V_s=2200V$

Output power is half of the input power i.e. $P_s=0.5P_p$

$\therefore$ $V_s{I}_s=0.5V_p{I}_p$

$\therefore$ $2200\times I_s=0.5\times 220\times 5$

$⟹$ $I_s=0.25A$