When we talk about something being "magnetic," we're usually referring to its ability to attract certain materials, such as iron or steel. This property is due to the presence of a magnetic field, which is a region around a magnet where its influence can be felt. Magnets have two poles, known as the north pole and the south pole. Like poles repel each other, while opposite poles attract each other.
Permanent Magnets: These are materials that are magnetized and retain their magnetic properties. Common examples include bar magnets, horseshoe magnets, and refrigerator magnets.
Electromagnets: These are magnets created by passing an electric current through a coil of wire. The strength of the magnetic field can be increased or decreased by changing the amount of current flowing through the wire.
Uses of Magnets
Magnets have a wide range of practical applications, including:
Give an example of a permanent magnet. Answer: A bar magnet.
What is an electromagnet and how is it different from a permanent magnet? Answer: An electromagnet is created by passing an electric current through a coil of wire. Its magnetism can be turned on and off by controlling the flow of electric current, unlike permanent magnets.
The Living Environment: Students understand that cells are the basic unit of life, that all life as we know it has evolved through genetic transfer and natural selection to create a great diversity of organisms, and that these organisms create interdependent webs through which matter and energy flow. Students understand similarities and differences between humans and other organisms and the interconnections of these interdependent webs.
Cells: Students describe how living things are made up of one or more cells and the ways cells help organisms meet their basic needs.
Give examples of organisms that consist of a single cell and organisms that are made of a collection of cells.