Magnetism1 and electricity2 are forces generated by the movement of electrons. They are both electromagnetic forces – the interplay of these two forces is the basis for many modern technologies. Electromagnets3 are magnets4 that are generated by electric fields. They have the advantage over regular magnets in that they can be switched on and off.
Electromagnets can be created by wrapping a wire around an iron5 nail and running current6 through the wire. The electric field7 in the wire coil creates a magnetic field8 around the nail. In some cases, the nail will remain magnetised even when removed from within the wire coil. Electromagnets are fundamental to many modern technologies.
In this activity, students build a simple electromagnet9.
By the end of this activity, students should be able to:
- build a simple electromagnet
- explore the influence of different variables on the effectiveness of the electromagnet
- work methodically to adapt their design to improve the electromagnet function.
Download the Word file (see link below) for:
- background information for teachers
- student instructions.
Nature of science
The NZC ‘Investigating in science’ strand of the nature of science10 requires teachers to provide students with opportunities to extend their experiences and personal explanations of the natural world through exploration, play, asking questions and discussing simple models. This activity provides such opportunities.
Activity ideas
Other activities on the SLH that explore magnetism include Probing fridge magnets, Make an electric motor, Investigating magnetism and Making a weather vane and compass.
Related content
There are several articles and a PLD session related to magnetism. They include Introducing magnetism, Using magnetism, Geothermal power, Superconductivity, Magnetic resonance imaging (MRI) and Exploring magnetism.
- magnetism: A force created by the motion of electrons, generating a magnetic field that influences magnetic objects such as iron and other metals.
- electricity: A general term that includes a variety of phenomena resulting from the presence and flow of electrical charge.
- electromagnet: A magnet consisting of a coil of insulated wire wrapped around a steel or iron core that is magnetised when a current flows through the wire.
- magnet: An object that generates a magnetic field that can influence magnetic objects such as iron and other metals.
- iron: A chemical element with the symbol Fe.
- current: The flow of electric charge through a conductor.
- electric field: Any region where a charged object experiences an electric force.
- magnetic field: The zone around a magnet in which a magnetic force can be detected.
- electromagnet: A magnet consisting of a coil of insulated wire wrapped around a steel or iron core that is magnetised when a current flows through the wire.
- nature of science: The Nature of Science (NoS), is an overarching and unifying strand of the New Zealand science curriculum. Through it, students develop the skills, attitudes and values to build a foundation for understanding the world around them – understanding how science works in order to make links between scientific knowledge and everyday decisions and actions.
