Physics
Magnetic crane: hold and release
Lift steel with an electromagnet and test the cost of a wider air gap.
Try this
Move the trolley, then reduce coil voltage. The load falls when magnetic force can no longer support it. Lower the magnet to pick it up again.
The model and its limits
Lumped magnetic circuit with an air gap, saturation cap, RL coil and pendulum load. Uniform pole field; no field-resolved FEM or steel hysteresis.
Equations used in the module
Equations L I′ + R I = V F = B² A / (2μ_0)
