The strength of the magnetic field is increased by adding more coils to the wire and placing a metal bar within the coils.
The given problem is based on the concept and fundamentals of the magnetic strength in a current-carrying coil of wire. The current-carrying wire in a coiled form is known as Solenoid.
And the mathematical expression for the magnetic field in a solenoid is,[
Here,
B is the strength of the magnetic field.
is the magnetic permeability of free space.
N is the number of coils.
The strength of the magnetic field will increase by increasing the number of coils and placing the metallic slab (it will increase magnetic permeability) within the coils.
Thus, we can conclude that the strength of the magnetic field is increased by adding more coils to the wire and placing a metal bar within the coils.
learn more about the magnetic field here:
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