(b) With a current of 0.38 A, the average velocity of an electron in the wire is 5.5  10-6 m s-1 and the average magnetic force on one electron is 1.4  10-25 N. Calculate the flux density B of the magnetic field.

B = 0.159 T

Explanation:

Given that,

Current, I = 0.38 A

The average velocity of the electron,

The average magnetic force on the electron,

We need to find the flux density B of the magnetic field. We know that the magnetic force is given by :

Put all the values,

So, the required flux density of the magnetic field is 0.159 T.

c) up is the direction the magnetic force is acting on the charge.

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia