Question

The magnetic dipole moment of Earth has magnitude 8.00 × 1022 J/T. Assume that this is produced by charges flowing in Earth's molten outer core. If the radius of their circular path is 3470 km, calculate the current they produce

Answer 1

Step-by-step explanation:

Dipole moment of a coil carrying current i with area A

M = i A , M is magnetic moment , i is current and A is area of the coil.

A = π R²

= 3.14 x ( 3470 x 10³ )²

= 3.78 x 10¹³ m²

8.00 x 10²² = 3.78 x 10¹³ x i

current i = 8.00 x 10²² / 3.78 x 10¹³

= 2.11 x 10⁹ A .