These are great for demonstrating magnetic induction/braking. Find yourself a good sized rare earth magnet and move it across the surface of the bar...you will feel the drag of the opposing field generated by induced current in the bar by the moving magnetic field.
Did you weigh it? Weigh yourself, write down the weight, weigh you holding the bar, subtract the first weigh from the second to get the bar weight.
On a regular bathroom scale it should weigh 6.85 pounds.