You are given two infinite, parallel wires each carrying current I. The wires are separated by a distance d, and the current in the two wires is flowing in the same direction. This problem concerns the force per unit length between the wires.

What is the force per unit length F/L between the two wires?

Explanation:

Since current is flowing in the same direction in both the wires , they will attract each other .

Magnetic field due to first wire on second wire

B = (μ₀ / 4π) x 2I / d  , I is current on first wire and d is distance of second wire

Force on length L on second wire

F = B I L , B is magnetic field , I is current in second wire and L is length of second wire .

force per unit length of second wire

F/L = B I

= (μ₀ / 4π) x 2I / d X I

= 10⁻⁷ x 2 x I² / d

The same force will apply on first wire due to second wire as action and reaction forces are equal and opposite.

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

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