Question

a circular loop has a radius 10 cm and it is carrying a current of 0.1 A. Calculate its magnetic moment.

Answer 1

Given :

• Radius of circular loop = 10 cm
• Current = 0.1 A

To find :

• Magnetic moment of the loop

Solution :

• Let the radius of the loop be r, the current carried by it be i and the magnetic moment be μ.

     ∴ r = 10 cm = 0.1 m

        i = 0.1 A

• We know that, magnetic moment is the product of the current and the area of the loop.

     ∴ μ = i × A

• Area of a circle is,

        A = π.r²

     ∴ A = π × (0.1)²

     ∴ A = 0.0314 m²

• Substituting the value of A,

        μ = (0.1) × (0.0314159)

           = 0.00314159 A.m²

     ∴ μ = 3.14159 × 10⁻³ A.m²

Answer : The magnetic moment will be 3.14159 × 10⁻³ A.m² .