Science - Energy Investigation 2 - The Force of Magnetism
Part 1 - Magnets and Materials
Students discover that iron-containing objects stick to permanent magnets; other objects do not. They generate a rule for magnetic interaction with materials: If a magnet sticks to an object, that object is most likely made of iron or its alloy, steel. Students go outdoors and use their magnets as iron detectors.
Part 2 - Magnetic Fields
Students observe that the two sides (poles) of magnets are different, attracting or repelling one another, depending on orientation. Students work with magnets and other objects to discover that magnetism acts through air, most metals, and all nonmetals. They also discover that bringing a magnet close to a piece of iron induces magnetism in the iron. Students learn that these effects are manifestations of the invisible magnetic field that surrounds every magnet.
Part 3 - Magnetic Force
Students use a balance to measure the force of attraction between magnets. They increase the distance between the magnets and remeasure the force. Students learn that the force of attraction between magnets decreases as the distance between them increases.