.1 Newton's First Law

• Newton’s First Law: If the resultant force acting on an object is zero and:

  the object is stationary, the object remains stationary

  the object is moving, the object continues to move at the same speed and in the same direction. So the object continues to move at the same velocity
• So, when a vehicle travels at a steady speed the resistive forces balance the driving force
• So, the velocity (speed and/or direction) of an object will only change if a resultant force is acting on the object.
• The tendency of objects to continue in their state of rest or of uniform motion is called inertia