5.1a The position of an object can be described by locating it relative to another object
or the background (e.g., on top of, next to, over, under, etc.).
5.1b The position or direction of motion of an object can be changed by pushing or
5.1c The force of gravity pulls objects toward the center of Earth.
5.1d The amount of change in the motion of an object is affected by friction.
5.1e Magnetism is a force that may attract or repel certain materials.
5.1f Mechanical energy may cause change in motion through the application of force and
through the use of simple machines such as pulleys, levers, and inclined planes.