4.1 Development of Force Concept

• Dynamics - study of forces that cause objects and systems to move
• Force - a push or pull
• Force is a vector
• Free Body Diagram - technique used to illustrate all external forces acting on a body
• Only external forces are shown on an free-body diagram since they are the only ones in motion (don't show internal forces)
• Restoring Force - uses force it exerts to pull itself back to relaxed shape
• Magnetism - magnetic force between two wires carrying electric current
• We have a standard force (force we are primarily focusing on), and the magnitudes of all other forces are called multiples of this standard unit force