Answer:
The width of the sheet is

Step-by-step explanation:
From the question we are told that
The distance of point P above a large sheet of metal is

The current on the large metal sheet is

The distance of the the point P below a long wire

The current on the long wire is

The magnetic field at P is

Generally magnetic field of P long wire is mathematically represented as

Generally magnetic field of P large sheet of meta is mathematically represented as

Where K is the current per unit width
The total magnetic field at P is

Making K the subject of formula

Substituting values


Generally K is mathematically represented as

Where w is the width of the large sheet
Therefore the width of the metal sheet


