Project Summary

   The purpose of this experiment was to observe the effects of a magnetic field on a ferrofluid by varying the field’s strength and direction. In addition to successfully observing these effects, the chemical reaction between iron and ferric chloride and between the ferrous chloride, ferric chloride, and ammonia in the making of iron nanoparticles was also observed. 

   The ferrofluid was synthesized via boiling ammonium hydroxide and a solution of ferric and ferrous chloride with oleic acid as a capping agent which coated the particles so that they would not agglomerate. This was important because the particles had to be small enough to overcome the forces of gravity and magnetic fields and remain in suspension. A test apparatus was constructed to control the distance and angle of the magnet in relation to the ferrofluid using wood, plastic, and LEGO parts (no metal). A camera was then used to capture images of the fluid’s shape and orientation as it responded to the magnetic field. The pictures were taken with the magnet at distances of: 14, 12, 10, 8, 6, 5, 4, and 3cm and at angles of 90, 70, 50, and 30degrees.

   The results of this project showed that the distance of the magnet directly affected the angle at which the ferrofluid would orient itself. It was seen that the force acting on the fluid was the sum of the magnetic and gravitational forces and inversely proportional to the distance of the magnet. This knowledge could be used to control ferrofluids and form manipulatable liquid mirrors.

YouTube Video