A lifting magnetic system is shown in the figure. The magnetic core has a square cross section of 5 x 5 cm². The coil has 200 turns and a resistance of 6 Q2. The permeability of the magnetic core → ∞ and you can ignore fringe effects in the air gap. The air gap is held at 5 mm and a de source of 100 V is connected to the coil. A. Determine the energy stored in the magnetic system (Wfta) B. Determine the corresponding magnetic lifting force (ffia) Hint: consider using the energy equation that involves integrating over the volume of the air-gap in your analysis