Newton's First Law

• What do Newton's laws of motion describe?

  The relationship between forces and motion
• What does Newton's First Law state?

  An object remains at rest or constant velocity unless acted on
• What happens to an object at rest according to Newton's First Law?

  It remains at rest unless acted upon
• What happens to an object moving with constant velocity according to Newton's First Law?

  It continues moving at that velocity unless acted upon
• What is required to change the motion of an object?

  A resultant force
• What can a resultant force do to an object?

  Speed it up, slow it down, or change direction
• What happens if the forces on a body are balanced?

  The body must be at rest or moving at constant velocity
• What does it mean if the resultant force is 0?

  The forces acting on the body are balanced
• How can forces be easier to analyze?

  By splitting them into horizontal and vertical components
• What does it mean if the forces acting to the left equal the forces acting to the right?

  The forces are balanced horizontally
• What does it mean if the forces acting upward equal the forces acting downward?

  The forces are balanced vertically
• What is the resultant force?

  The vector sum of all forces acting on a body
• If a car is moving at constant velocity with no external forces, what is the value of the frictional force?

  Frictional force F is zero

  
• How is Newton's First Law often rephrased?

  A body will remain at rest or constant velocity unless acted on
• Why was Newton's First Law revolutionary?

  It challenged the belief that moving objects slow down
• What misconception persists about motion and forces?

  That moving objects naturally slow down