Question

The field around a long, straight wire is:

parallel to the wire
radial to the wire
perpendicular to the wire
concentric with the wire

Answer 1

concentric with the wire

Step-by-step explanation:

Answer 2

Concentric with the wire

Step-by-step explanation:

The magnetic field around a long, straight current-carrying wire forms concentric lines around the wire itself. The magnitude of the field is given by:

`B=(\mu_0 I)/(2\pi r)`

where

`\mu_0` is the magnetic permeability

I is the current in the wire

r is the distance from the wire

The direction of the lines of the field can be determined by using the right-hand rule: the thumb of the right hand points in the same direction as the current, and the other fingers (wrapped around the thumb) gives the direction of the field lines.