Question

A step up transformer is connected to an ac mains supply of 220 V to operate at 11000 V, 88 watt. The current in the secondary circuit, ignoring the power loss in the transformer, is

• A. 8 mA
• B. 4 mA
• C. 0.4 A
• D. 4 A

Answer 1

Answer: (A)

8 mA

Answer 2

Ignoring power loss, power in primary = power in secondary. Power (P) = VI Primary voltage ($V_p$) = 220 V Secondary voltage ($V_s$) = 11000 V Power (P) = 88 W Secondary current ($I_s$) = ?

88 = 11000

$\implies i = \frac{88}{11 \times 10^3} = 8 \times 10^{-3} \text{ A}$

$\implies i = 8 \text{ mA}$