![]() ![]() These materials are based on mixtures of iron, nickel or cobalt as these are the only three known ferromagnetic elements. fridge magnets, door catches and magnetic toys) are manufactured from materials which areįerromagnetic. The vast majority of magnets we encounter (e.g. The other two forces areĮlectrostatic and gravitational (see the focus idea ![]() Magnetic attraction and repulsion is one of three fundamental non contact forces in nature. ![]() However, the vast majority of the magnetic fields around us are simply too weak to cause any observed effects or remain ‘removed from us’ because they are utilised in more complex machines like electric motors and computer hard drives. the Earth’s magnetic field and magnetic fields produced by electric current). Magnetic fields in our everyday experiences (e.g. Maloney, O’Kuma, Heieggelke & Van Heuvelen (2001) Scientific view Understandably their naive model has no predictive or explanatory power and they typically do not perceive the need to do more than identify and label the attractive or the less frequent repelling behaviour as magnetic. However, many younger students simply associate magnetism with a ‘pulling force’. It is well established that older students hold a range of views about magnetism that vary considerably in their sophistication, ranging from magnetic models with surrounding ‘clouds’ of action to ideas about ‘electric rays’ and ‘fields’. Students’ confusion around non contact forces is explored in the focus idea For example, a balloon ‘rubbed’ with a cloth resulting in its attraction to another object is frequently described incorrectly by young students (and even some adults) as having been ‘magnetised’ in some way. To them, these often appear to be common experiences of the same invisible non contact force, usually only attraction. They do not see the need to discriminate between magnetic forces and electrostatic forces (or gravity). Many younger students are yet to form strong views or in many cases any views at all about how magnets interact with matter or each other. Toys very rarely make use of magnetic repulsion. wooden train carriages) or are used in simple children’s construction toys to allow them to quickly assemble more complex structures without the need for messy adhesives or difficult connections. Many children’s toys employ weak magnets to ‘stick’ materials together (e.g. Magnetic materials are regularly encountered around the home, often holding small objects on the kitchen fridge or keeping cupboards and fridge doors closed. Many young students will have had memorable but often confusing experiences with magnets and magnetic materials. Contrasting student and scientific viewsĬontrasting student and scientific views Student everyday experiences. ![]()
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