Why will a magnet attract an ordinary nail or paper clips but not a wooden pencil?

A magnet can only attract objects that are made of "ferromagnetic" materials (such as iron). A pencil is not made of ferromagnetic material and hence is not attracted to a magnet.

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A magnet attracts certain materials, such as iron, nickel, and cobalt, due to the presence of magnetic properties in these materials. When a magnet is brought close to a nail or paper clips, the magnetic field of the magnet interacts with the magnetic domains in the metal, causing them to align and create an attractive force between the magnet and the metal objects.

On the other hand, a wooden pencil does not contain any magnetic properties. Wood is composed primarily of non-magnetic materials, such as cellulose fibers, which do not have any interaction with magnetic fields. Therefore, a wooden pencil is not attracted to a magnet because it lacks the magnetic properties required for an attraction to occur.

To determine if a material is magnetic or not, you can perform a simple experiment. Bring a magnet close to the object in question and observe if there is any attraction. If the object is attracted to the magnet, it likely contains magnetic properties. Conversely, if there is no attraction, the object is non-magnetic.