Slader A long, straight wire carries a current of 5.20 AA. An electron is traveling in the vicinity of the wire. At the instant when the electron is 4.40 cmcm from the wire and traveling with a speed of 6.20×104 m/sm/s directly toward the wire, what is the magnitude of the force that the magnetic field of the current exerts on the electron?

Explanation:

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

where:

is the vacuum permeability

I is the current in the wire

r is the distance from the wire

In this case,

I = 5.20 A

r = 4.40 cm = 0.044 m

Therefore,

The direction of the field is along concentric circles centered in the wire.

The force exerted by a magnetic field on a moving charged particle is

where

q is the charge

v is the velocity of the particle

is the direction between v and B

In this problem:

is the magnitude of the charge of the particle

is the velocity

, because the electron is travelling towards the wire, so perpendicular to the lines of the magnetic field

Therefore, the magnitude of the force is:

it would be c. predictability