Question

We have seen that the heart produces a magnetic field, and that this can be used to diagnose problems with the heart. The magnetic field of the heart is a dipole field that is produced by a loop current in the outer layers of the heart. Suppose the field at the center of the heart is 90 pT (a pT is 10−12T ) and that the heart has a diameter of approximately 12 cm. What current circulates around the heart to produce this field?

Answer 1

Thus the current flowing is 8.8 x 10⁻⁵ A

Explanation:

The field at the center of circular current can be calculated by

B = $\frac{\mu _0 I}{r}$

here μ₀ is permeability constant and is equal to 4π x 10⁻⁷

I is the current in circular path and r is the radius of circle

Thus I =$\frac{90x10^-^1^2x12x10^-^2}{4\pi x 10^-^7 }$ = 8.8 x 10⁻⁵ A