Electricity & Magnetism

Pumping Iron

The flower-like patterns are created by magnetic fields acting on the black liquid. With the buttons and the knob, visitors tell a computer what pattern they want to see. The computer directs pulses of electric current through a coil, creating a magnetic liquid above it. The black liquid is made of magnetite (iron oxide) particles suspended in a carrier fluid. Magnetic fields attract the tiny magnetic particles, pulling them (and the carrier fluid) up against the force of gravity. .