Q 12-07-010NEETNEET 2021Top questionEasy
A step down transformer connected to an ac mains supply of $220$ V is made to operate at $11$ V, $44$ W lamp. Ignoring power losses in the transformer, what is the current in the primary circuit ?
Answer: (B) $0.2$ A
No losses, so primary power = $44$ W:
$$I_p = \frac{44}{220} = 0.2\ \text{A}$$
Solution by Sreeraj P, M.Sc Physics