Question

A student connects a long air cored-coil of manganin wire to a $100VD.C$. supply and records a current of $25amp$. When the same coil is connected across $100V,50Hz$ a.c. the current reduces to $20A$, the reactance of the coil is :-

• A. $4\Omega$
• B. $3\Omega$
• C. $5\Omega$
• D. None

Answer 1

The correct option is B $3\Omega$