Question

Repeat Exercise $\mathbf{22}\mathbf{.}\mathbf{5}$for a negative charge.

Short answer

(a) The direction of the magnetic field on a negative charge will be out of the page.

(b) The direction of the magnetic field on a negative charge will be towards the right or east direction.

(c) The direction of the magnetic field on a negative charge will be inwards to the page.

Step-by-step solution

Define the right-hand-rule for the magnetic force

Considering the image for a better understanding of the right-hand rule, the direction of the magnetic force on a moving charge is said to be perpendicular to the plane formed by the velocity of the particle and the magnetic field intensity.

the direction of the magnetic field for a negative charge is said to be in the opposite direction shown by the fingers of the right hand. See the arrangement shown in the below figure,

Explanation of the direction of the magnetic field

(a)

Considering the above Figure 22.52 (a) for a moving positive charge, according to the right-hand rule, if the palm points in the direction of the west and the thumb points towards the north then the fingers will point inwards to the page.

Therefore, the direction of the magnetic field on a negative charge will be outwards to the page.

(b)

Considering the above Figure 22.52 (b) for a moving positive charge, according to the right-hand rule, if the palm points downwards and the thumb points towards the south then the fingers will point west.

Therefore, the direction of the magnetic field on a negative charge will be towards the right (east) direction.

(c)

Considering the above Figure 22.52 (c) for a moving positive charge, according to the right-hand rule, if the palm points to the north and the thumb points towards the west then the fingers will point outward to the page.

Therefore, the direction of the magnetic field on a negative charge will be inwards to the page.