Question

A wire of certain length carries a steady current. It is bent first to form a circular coil of one turn. The same wire is next bent to form a circular coil of three turns. The magnetic flux density at the centre of coil caused by the current of same strength shall be-

• A. 9 times of its first value
• B. 1/9 times of its first value
• C. 3 times of its first value
• D. 1/3 times of its first value

Answer 1

Answer: (A)

9 times of its first value

Answer 2

B = for same wire B µ N²