|MadSci Network: Physics|
Interesting experiment. Magnetic attraction and electrical conductivity of metals are separate properties and are not necessarily directly proportional to each other. Conductivity is a measure of the ability of materials to give up electrons to promote electron flow. Magnetism is a polorized magnetic field around a metal. In your experiment, steel and aluminum are conductors, the balloon is a non-conductor. The relative conductivity of pure aluminum is 59 S/cm (Siemens/centimeter) compared to steel which is 3-15 S/cm. Since aluminum is a better conductor of electricity, it will dissapate the static electricity charge faster than steel resulting in releasing the balloon sooner. I hope this answers your question. Ref: http://www.amm.com/ref/ conduct.HTM http:// www.sciencemadesimple.com/static.html
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