If flux density is represented by 'B' and magnetic field is represented by 'H' in a magnetic circuit, then what will be the energy density in the magnetic field?

Explanation:

The energy density in a magnetic field is given by the formula:

\(\mu={BH\over 2}\)

where:

• u is the energy density in joules per cubic meter
• B is the flux density in teslas
• H is the magnetic field strength in amperes per meter

Therefore, the correct answer is option 4, BH/2.

Here is a brief explanation of why the other options are incorrect:

• Option 1, BH2/2, is the energy density in the magnetic field of a free space.
• Option 2, BH, is the force per unit length on a conductor carrying a current in a magnetic field.
• Option 3, BH2, is the energy density in the magnetic field of a material with a relative permeability of 1