Question

a wire of magnetic dipole moment M and L is bent into shape of a semicircle of radius r what will be its new dipole moment

Answer 1

magnetic moment M equals m×pie r

Answer 2

answer : new dipole moment = 2ML/π

a wire of magnetic dipole moment M and L is bent into shape of a semicircle of radius r
then, Length of wire = half of circumference of circle
L = πr => r = L/π ,then, 2r = 2L/π

now, dipole moment = magnetic moment × minimum separation between dipoles

here magnetic moment = M
minimum separation between dipoles =2r = 2L/π
so, new dipole moment = M × 2L/π = 2ML/π