Newton's First Law

• What does Newton's First Law state?

  An object has a constant velocity unless acted on by a resultant force
• If a resultant force acts on the object, it will accelerate:

  • acceleration is change in velocity over time
  • so velocity will change
  • either the direction or speed of the object will change
• If no resultant force acts on the object:

  • and the object is stationary, it will remain stationary
  • and the object is moving, it will continue to move at the same velocity
• What is inertia?

  Tendency for objects to continue in uniform velocity or stay at rest