Newton’s Laws

• What does Newton's first law state about resultant force?


  A resultant force is required to change the motion of an object
• What occurs if the resultant force on a moving object is zero?


  The object will continue moving at the same velocity
• What happens to a stationary object if the resultant force is zero?


  The object will remain stationary
• What does Newton's second law state about non-zero resultant force?


  A non-zero resultant force causes an object to accelerate
• If a particle has unbalanced forces acting on it, what will happen?


  The particle will accelerate in the direction of the resultant force
• What are the five possible outcomes of acceleration depending on the initial motion of an object?


  1. Start moving to the right
  2. Speed up if moving to the right
  3. Slow down if moving to the left
  4. Stop if moving to the left slowly
  5. Change direction without speed change
• How is acceleration defined mathematically?


  Acceleration is the change in velocity divided by the change in time
• Why does the moon accelerate even though its speed remains constant in circular motion?


  Its direction is constantly changing
• What force acts on the moon to keep it in orbit around the Earth?


  The gravitational pull of the Earth
• What does the size of the resultant force relate to in Newton's second law?


  The size of the resultant force is directly proportional to the acceleration it causes
• What is the equation that relates force, mass, and acceleration?


  $F =$$m \cdot a$
• If a particle has a mass of 0.25 kg and experiences a resultant force of 12 N, what is its acceleration?


  $48 \text{ m/s}^2$
• What is inertia in relation to Newton's first law?


  Inertia is the tendency for the motion of an object to remain unchanged
• How is an object's inertial mass defined?


  An object's inertial mass measures how difficult it is to change its velocity
• How do you calculate inertial mass using Newton's second law?


  By dividing force by acceleration
• What does a large mass indicate about an object's inertia?


  A large mass indicates a lot of inertia, requiring a big force to change its velocity
• What does Newton's third law state about the forces between two interacting objects?


  The forces they exert on each other are equal and opposite.
• What does the "equal" part of Newton's third law refer to?


  It refers to the magnitude of the two forces.
• What does the "opposite" part of Newton's third law refer to?


  It refers to the direction of the two forces.
• If you push a box with a force of 100 newtons, what force does the box exert on you?


  The box exerts an equal force of 100 newtons on you.
• What is the term used for the force that the box exerts on you?


  Normal contact force.
• What determines whether you or the box will move when you push it?


  It depends on the mass of the box and the force applied.
• What is the equation related to Newton's second law?


  The equation is \( F = ma \).
• What is required for an object to be accelerated and move?


  You need either a high force or a small mass.
• What generally happens to the smaller object when a force is applied?


  The smaller object will generally move most.
• What are the key concepts of Newton's third law of motion?


  • Forces between two objects are equal and opposite.
  • Magnitude of forces is equal.
  • Direction of forces is opposite.
  • Example: Pushing a box results in equal force exerted back.
• How does mass affect movement when a force is applied?


  • Smaller mass: more likely to move.
  • Larger mass: less likely to move.
  • Medium mass: may result in partial movement of both objects.