Magnets

After an investigation where students observe magnets interacting with magnetic and non-magnetic objects, students write an opinion about why they think the magnets attract certain objects and not others.

Students plan and create a story where they imagine themselves to be magnetized. Have them consider situations where they would be attracted or repelled by everyday objects.

Give each student or small group a question about magnetism and access to several sources. Have them locate an answer to the question and be prepared to share it with the class.

Analyze several everyday materials and sort into magnetic and non-magnetic. Count and compare the numbers in each category.

Conduct the experiment How Strong Is Your Magnet? Students will record data and graph results. The x-axis (horizontal) is for the distance from the magnet (that is, the number of layers of tape beginning with zero); the y-axis (vertical) is for the strength of the magnet (number of paper clips it can hold).

Follow the directions for Making An Electromagnet. To increase the strength of the electromagnet, increase the number of wire coils around the nail and record the number of paper clips you can pick up. Each pair of students will keep a table of the number of coils and number of paperclips. Then collect and average student findings to create a class chart.

Matter can be described and classified by its observable properties.

Examples of problems could include constructing a latch to keep a door shut and creating a device to keep two moving objects from touching each other.

Electric and Magnetic forces between a pair of objects do not require that the objects be in contact.

Examples of magnetic force could include the force between two permanent magnets, the force between an electromagnet and steel paper clips, and the force exerted by one magnet versus the strength exerted by two magnets. Examples of cause and effect relationships could include how the properties of the objects and the distance between objects affect strength of the force, and how the orientation of magnets affects the direction of the magnetic force.

Energy can be transferred from place to place by electric currents, which can then be used locally to produce motion, sound, heat or light. Possible solutions to a problem are limited by available materials and resources (constraints). The success of a designed solution is determined by considering the desired features of a solution (criteria.)

Matter of any type can be subdivided into particles that are too small to see, but even then the matter still exists and can be detected by other means.

Emphasis is on the analysis of data from Earth-based instruments, space-based telescopes, and spacecraft to determine similarities and differences among solar system objects.

Forces that act at a distance (magnetic) can be explained by fields that extend through space and can be mapped by their effect on a test object.

Examples of this phenomenon could include the interactions of magnets. Examples of interactions could include first-hand experiences or simulations.

Electric and magnetic (electromagnetic) forces can be attractive or repulsive, and their sizes depend on the magnitudes of the charges or magnetic strengths involved and on the distances between the interacting objects.

Examples of devices that use electric and magnetic forces could include electromagnets or electric motors. Examples of data could include the effect of the number of turns of wire on the strength of an electromagnet, or the effect of increasing the number or strength of magnets on the speed of an electric motor.

Substances are made from different types of atoms, which combine with one another in various ways.