Like the gravitational force, the force between two of these objects decreases proportionally to r squared.
Earnshaw's theorem applies to these objects, stating that no arrangement of them will result in a stationary equilibrium of charge. Like the gravitational force, the force between two of these objects decreases proportionally to r squared. These objects switch from one type of their namesake property to another at the Curie temperature. Their strength is measured in Teslas, and permanent ones create a constant namesake field. For 10 points, name these objects that are commonly bar shaped or U-shaped and can be found on many refrigerators.
Earnshaw's theorem applies to these objects, stating that no arrangement of them will result in a stationary equilibrium of charge.
magnets [accept all specific types of magnets before "Curie," and accept only magnet after]