A nail would be the best answer.
Yes
The iron filings experiment demonstrates that a magnet's force can pass through certain materials. Placing iron filings on a piece of paper and then placing a magnet underneath the paper will cause the filings to align along the magnetic field lines, showing that the magnet's force is able to pass through the paper.
Lines of force go from a North pole of a magnet to the South pole external to a magnet, and through the magnet itself. This path is the magnetic circuit. It may be diverted and distorted by magnetic materials nearby.
When the material reaches its melting point, whatever that may be for the given material, it will go through fusion (will change from solid state to liquid state). Once the material reaches its boiling point it will go through evaporation (will change from liquid state to a gaseous state).
No magnets are in them when you buy them from electrical stores. People can buy special "magnet balls" for use in washers which mean they don't have to use so much wash detergent. (= cleaning chemicals) The case metal of these appliances is usually steel, which contains iron, which is a magnetic material.
Iron is a ferrous material, and aluminum is non-ferrous. A magnet would separate the two materials as the iron would be attracted to the magnet while the aluminum filings would not. The term ferrous basically refers to any material which contains iron.
opaque
No, imported mattresses do not have to go through customs because they are not considered a hazardous material.
You will generate electricity. As the wire cuts through the magnetic field.As the magnet is moved, there will be an induced electro-motive force (EMF) which can cause a current in the coil. Once the magnet stops moving, the current will go to zero.
No, gases cannot go through every material. The ability of a gas to pass through a material depends on the size of the gas molecules and the structure of the material. For example, gases can pass through porous materials like membranes, but not through solid barriers like metals.
Yes, light can pass through an opaque material if it is transparent or translucent. However, if the material is completely opaque, light will not be able to pass through it.
Yes. Absolutely yes. A magnet forms something called a 'magnetic field' you can expiriment and view this easily by taking a piece of paper and applying a thin layer of iron shavings, then put a magnet below the paper, you will see the iron shavings adhere to the magnetic field of the magnet.