Question

$P$ and $Q$ are two circular thin coils of same radius and subjected to the same rate of change of flux. If coil $P$ is made up of copper and $Q$ is made up of iron, then the wrong statement is

• A. emf induced in the two coils is the same
• B. the induced current in $P$ is more than that in $Q$
• C. the induced current in $P$ and $Q$ are in the same direction
• D. the induced currents are the same in both the coils.

Answer 1

Answer: (D)

Induced emf is,
$\left[\because e = - \frac{d \varphi}{d t} = - A \frac{d B}{d t}\right]$
Therefore induced emf and direction of current does not depend on material of the coil but resistance of copper is less than iron therefore current in copper coil is more.