det er to typer magneter.... positivt og negativt ladet.
hvis rørepinnen løfter seg på ene siden, er det vel mest sannsynlig at ene magneten i røreren er snudd feil vei....
nøytralt metall vil uansett tiltrekkes, men en positiv magnet fraskyver en positiv, og motsatt. er pinnen positiv og ene magneten i røreren er positiv vill de frastøte hverandre som eksempel.
mens positiv og negativ vill forsterke samentrekkingen.
med en magnetisk rørepinne er vi egentlig ikke avhengige av magneter i røreren. (men det øker selvfølgelig effekten, hvis polariteten er riktig)
EDIT:
kopi wikkipedia....http://en.wikipedia.org/wiki/Magnet
Magnetic poles
Field of a cylindrical bar magnet calculated with Ampère's model
Although for many purposes it is convenient to think of a magnet as having distinct north and south magnetic poles, the concept of poles should not be taken literally: it is merely a way of referring to the two different ends of a magnet. The magnet does not have distinct north or south particles on opposing sides. If a bar magnet is broken into two pieces, in an attempt to separate the north and south poles, the result will be two bar magnets, each of which has both a north and south pole.
However, a version of the magnetic-pole approach is used by professional magneticians to design permanent magnets. In this approach, the divergence of the magnetization ∇M inside a magnet and the surface normal component Mn are treated as a distribution of magnetic monopoles. This is a mathematical convenience and does not imply that there are actually monopoles in the magnet. If the magnetic-pole distribution is known, then the pole model gives the magnetic field H (see also Demagnetizing field). Outside the magnet, the field B is proportional to H, while inside the magnetization must be added to H (see Units and calculations). An extension of this method that allows for internal magnetic charges is used in theories of ferromagnetism (see micromagnetics).
