A certain amount of current flows through a ringshaped coil with ___

A certain amount of current flows through a ringshaped coil with fixed number of turns.

How does the magnetic induction B varies inside the coil if an iron core is threaded into coi] without dimensional change of coil?

A. Decreases
B. Increases
C. Remains same
D. First increases and then decreases depending on the depth of iron insertion

Show Answer

Answer: B

Share your understanding of this question with the correct explanation.