Introduction Magnets have existed for hundreds of thousands of years and have been used by many different cultures throughout this time. Magnets have been useful throughout the years because they can hold two things together just through the force of the metal in the magnet. With the world’s constantly changing technology, electromagnets have been evolved from magnets and are more useful than a regular magnet but in order for an electromagnet to work, an electric current needs to be present
Whether a material is magnetic depends on the material’s atoms”. A material’s atoms can effect what different materials that the magnet can pick up. Everything in the universe is made up of atoms and electrons. The electron moves around the atom and as it does this, it creates a magnetic field. In materials such as aluminum and copper, the magnetic fields of those certain atoms delete each other making the materials not magnetic. “In materials such as iron, nickel, and cobalt, groups of atoms are in tiny areas called domains. The north and south poles of the atoms in a domain line up and make a strong magnetic field. The arrangement of domains in an object determines whether the object is magnetic or not”. Because magnetic materials contain domains, this makes the material magnetic and attract other magnetic objects. What are the different kinds of magnets? Magnets are made up of many different materials such as “iron, nickel, cobalt, or a mixture of these metals”. Ferromagnets are created with those metals and produce strong magnetic properties. “A mineral magnetite is an example of a naturally occurring ferromagnet” from the combination of stronger metals. Another kind of magnet is the electromagnet. This kind of magnet is made from an electric current and an electromagnet consists of an iron core. Magnets can also be classified as
The patellar reflex can be defined as the kicking movement of the lower leg which occurs with a sudden twitch when the patellar tendon of a person is tapped. This patellar tendon is present below a person's kneecap. This reflex happens only when the leg is bended. It is impossible for patellar reflex to occur if the leg is straight as the quadriceps muscles are already contracted and a sudden kicking movement of the leg in such state could not be elicited. The patellar reflex protects the quadriceps from stretching too much.
