5G30.12 - Para and Dia-magentic Force Measurement
To demonstrate the paramagnetic and diamagnetic properties of different materials using a microgram scale and a magnet.
Connect the microgram scale and make sure it is balanced. Place the magnet that is stuck to a washer onto the pan of the microgram scale (be careful not to push down on the pan of the scale). Place the platform supports on either side of the pan of the scale and lay the white platform piece across the supports. Close the doors of the scale and turn it on. Wait for the scale to equalize and make sure it is tared to zero grams.
When ready to make measurements, take one of the pieces of material that is attached to a string and carefully lower it from above onto the white platform and center it over the magnet location. Observe the reading on the scale. If the reading is positive, then the material is repeling the magnet, showing its diamagnetic properties. If the reading on the scale is negative, then the material is attracting the magnet, showing its paramagnetic properties.
Provided materials: Glass, Teflon, Bismuth, Graphite, Aluminum, Gadolinium
**Option: Provide cup of hot water and cold water to submerge the Gadolinium in, along with paper towels to dry it off, so that the effects of ferromagnetism and paramagnetism of this material can be explored.**
When ready, make sure the scale is on and the reading is tared to zero grams. Open the door to the top of the scale half-way. Take one of the provided materials and slowly lower the material onto the platform above the magnet. Observe the reading on the scale.
If the scale reads a positive value, then the material is repeling the magnet below, showing diamagnetic properties of the material.
If the scale reads a negative value, then the material is attracting the magnet below, showing paramagnetic properties of the material.
Aluminum is an interesting material due to the presence of eddy currents while the material is in motion near a magnetic field. When the aluminum block is stationary, then the correct reading on the scale will be evident.
Gadolinium has a magnetic transition that occurs at 20 degrees C. Above 20C, the material is strongly paramagnetic. Below 20C, the material is strongly ferromagnetic. Due to the strength of the magnetic properties of this material, it is constructed so that it does not lay on top of the platform, but rather is suspended approx 1" from the top of the platform. Otherwise, the magnet will lift off of the pan of the scale and read nothing on the scale.