Newton's First Law of Motion

• What does Newton's first law of motion state about stationary objects?

  If the resultant force acting on a stationary object is zero, then the object will remain stationary.
• What does Newton's first law of motion state about moving objects?

  If the resultant force acting on a moving object is zero, then the object will continue moving in the same direction at the same speed.
• What are the key concepts of Newton's first law of motion?

  • Resultant force of zero on stationary object: remains stationary
  • Resultant force of zero on moving object: continues moving with same velocity
• How does a resultant force affect a stationary object?

  A resultant force causes the object to accelerate in the direction of the force.
• What happens to an object moving at a constant speed when a resultant force acts on it?

  A resultant force can cause the object to decelerate or change direction.
• What are the effects of a resultant force on an object in motion?

  • Causes acceleration in the direction of the force
  • Can cause deceleration if opposing a driving force
  • Can change the direction of the object's motion
• What is the driving force of a car moving at a constant speed?

  The driving force of the engine.
• What must be true for a car to maintain a constant speed?

  There must be an equal force acting to the right to balance the driving force.
• What are resistive forces acting on a moving car?

  • Friction with the air
  • Friction with the road
• What does a resultant force of 50 Newtons acting to the right do to a stationary object?

  It causes the object to accelerate to the right.
• What effect does a resultant force have on an object moving at a constant speed?

  It causes the object to decelerate.
• How can a resultant force change an object's direction?

  • By applying a force at an angle to the direction of motion
  • Causes the object to accelerate in the new direction
• What is the key fact about the velocity of an object in relation to resultant force?

  The velocity of an object will only change if a resultant force is acting on the object.