A coil is wound with 50 turns and a current 8A produces a flux of 200μWb. Calculate the inductance of the coil

• A. 2.5 mH
• B. 0.25 mH
• C. 1.25 mH
• D. 0.125 mH

Answer: (C)

The inductance of the coil is given by the relation
L = Nφ/I
Where
N = number of turns = 50
φ = flux = 200μWb
I = current = 8 A
L = 50 × 200 ×  10−6 ⁄ 8
L = 1.25 mH