Magnetism

Magnetism - Magnetism is a force of attraction or replusion that acts at a distance. It is due to a magnetic field, which is caused by moving electrically charged particles or is inherent in magnetic objects such as a magnet.

Magnetism - A magnet is an object that exhibits a strong magnetic field and will attract materials like iron to it. Magnets have two poles, called the north (N) and south (S) poles. Two magnets will be attacted by their opposite poles, and each will repel the like pole of the other magnet. Magnetism has many uses in modern life.

Current Electricity

Electric Current - The Electric current is a flow of electric charge through a conductive medium.

In electric circuits this charge is often carried by moving electrons in a wire. It can also be carried by ions in an electrolyte, or by both ions and electrons such as in a plasma.

The SI unit for measuring the rate of flow of electric charge is the ampere, which is charge flowing through some surface at the rate of one coulomb per second. Electric current is measured using an ammeter.

Static Electricity

Static electricity is an excess of electric charge trapped on the surface of an object. The charge remains until it is allowed to escape to an object with a weaker or opposite electrical charge, such as the ground, by means of an electric current or electrical discharge. Static electricity is named in contrast with current electricity, which flows through wires or other conductors and transmits energy.