Question

The magnetic moment associated with a circular coil of 35 turns and radius 25 cm, if it carries a current of 11 A is

• A. 72.2 A m2
• B. 70.5 A m2
• C. 74.56 A m2
• D. 75.56 A m2

Answer 1

Answer: (D)

75.56 A m2

Answer 2

Given N = 35, r = 25 cm

$= 25 \times 10 ^ { - 2 } \mathrm { mI } = 11 \mathrm {~A}$

The magnetic moment associated with this circular coil

$\mathrm { M } = \mathrm { NIA } = \mathrm { NI } \pi \mathrm { r } ^ { 2 } = 35 \times 11 \times .314 \times \left( 25 \times 10 ^ { - 2 } \right) ^ { 2 }$