In an iron cored coil the iron core is removed so that the coil becomes an air cored coil. The inductance of the coil will_____________?
Correct answer: B. decrease
- A. increase
- B. decrease
- C. remain the same
- D. initially increase and then decrease
Explanation
Inductance is proportional to the core permeability, as shown by L = μN²A/l. Removing an iron core replaces its high permeability with the much lower permeability of air, so inductance decreases.
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