Question

The magnetic dipole moment of Earth is 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 3350 km, calculate the current they produce.

Answer 1

To solve the problem it is necessary to use the concepts and expressions related to the magnetic dipole moment.

It is usually defined by,

`\mu = IA`

Where,

`\mu =` Magnetic Dipole Moment

I = Current

A = Area

In this way re-arrange for the current and replacing,

`I = (\mu)/(A)`

`I = (8*10^(22))/(\pi R^2)`

`I = (8*10^(22))/(\pi * (3350*10^3)^2)`

`I = 7.1285*10^9A`

Therefore the current is
`7.1285*10^9` Amperes