Some pacemakers employ magnetic reed switches to enable doctors to change their mode of operation without surgery. A typical reed switch can be switched from one position to another with a magnetic field of 5.0x10-4 T. What current must a wire carry if it is to produce a 5.0x10-4 T field at 0.50m?I = ? kA

Respuesta :

Answer:

1.25 kA

Explanation:

The magnitude of the magnetic field produced by a current-carrying wire is given by:

[tex]B=\frac{\mu_0 I}{2 \pi r}[/tex]

where

[tex]\mu_0 = 1.26 \cdot 10^{-6} H/m[/tex] is the vacuum permeability

[tex]I[/tex] is the current in the wire

r is the distance from the wire at which the field is calculated

In this problem, we have:

[tex]B = 5.0\cdot 10^{-4} T[/tex] is the intensity of the magnetic field

[tex]r = 0.50 m[/tex] is the distance from the wire

Re-arranging the equation, we can find the intensity of the current in the wire:

[tex]I=\frac{2 \pi r B}{\mu_0}=\frac{2 \pi (0.50 m)(5.0\cdot 10^{-4}T)}{1.26\cdot 10^{-6} H/m}=1246 A=1.25 kA[/tex]