Question

What is the direction of a current that experiences the magnetic force shown in each of the three cases in Figure${}^{\mathbf{22}\mathbf{.}\mathbf{54}}$, assuming the current runs perpendicular to B?

Short answer

(a) The current will be flowing to the left (west).

(b) The current will be flowing out of the page.

(c) The current will flow in an upward direction (north).

Step-by-step solution

Concept Introduction

The magnetic impact on moving electric charges, electric currents, and magnetic materials is described by a magnetic field, which is a vector field. In a magnetic field, a moving charge experiences a force that is perpendicular to both its velocity and the magnetic field.

The Direction of a Current

The right-hand rule will be used to identify the current direction.

The palm will be aligned with the force direction, the fingers will be aligned with the field direction, and then the thumb will be pointing in the direction of the current.

(a)

The current will point to the left or in the west direction if the force is pointing upwards and the field is pointing outwards.

(b)

The current will point out of the page if the force is directed upwards and the field is pointed to the right.

(c)

The current will be pointing upwards since the force is directed to the right and the field is pointing into the page.