 Content: We will learn about magnetic properties.  Language: We will read new information about the Earths magnetosphere. We will classify prior knowledge in our notes and confirm our understanding of magnetism.

 Magnetism ◦ the phenomenon of physical attraction for iron observed in magnets, inseparably associated with moving electricity and characterized by fields of force Magnetic force increases as magnets move closer together!

 A magnetic field surrounds a magnet and is strongest at the poles; it is produced by the motion of electric charge.  Both the orbital & spinning motion of every electron in an atom produce magnetic fields.

 Magnetic field lines: arrows drawn from north to south poles representing the magnetic field.  Number of field lines indicates the relative strength of the magnet

 All magnets have a north pole and a south pole  Like poles repel. Unlike poles attract

 A compass needle is a small bar magnet that can freely rotate  A compass needle always points north, or rather is north-seeking

 The northern lights (aurora borealis) & southern lights (aurora australias) are results from the interaction between the solar wind and earth’s magnetic field (makes the air glow).

 Microscopic groups of atoms with aligned magnetic poles

 Materials in which the domains will line up in order to form a magnetic field ◦ Examples: iron, cobalt, and nickel

 Material that keeps its magnetic properties, even when it is not close to other magnets  Made by placing a magnetic material in a strong magnetic field, which causes the domains to remain aligned.

 The domains of temporary magnets are only aligned when the material is influenced by a magnetic field. (ex. Refrigerator, white board)

 Electromagnet – temporary magnet that is created by electric current flowing in a wire, usually in the form of a wire coiled around a piece of iron Magnetic field is present only when current is flowing in the wire coil

Strength of an electromagnet depends on:  amount of current in the wire  amount of iron or steel in the core  number of turns in the coil

 Electromagnetic induction – the production of an electric current by moving a loop of wire through a magnetic field or moving a magnet through a wire loop (which changes the magnetic field near the conductor; no battery!)