Newton's Laws of Motion

Newton's Laws

• First Law (Law of Inertia):
  • An object at rest will remain at rest, and an object in motion will continue to move with a constant velocity, unless acted upon by an external force.
  • Inertia: the tendency of an object to resist changes in its motion.
• Second Law (Force and Acceleration):
  • Force (F) is equal to the mass (m) of an object multiplied by its acceleration (a): F = ma.
  • The more massive an object, the more force is required to produce a given acceleration.
• Third Law (Action and Reaction):
  • For every action, there is an equal and opposite reaction.
  • When two objects interact, the forces they exert on each other are equal in magnitude and opposite in direction.

Gravity

• Definition: Gravity is a fundamental force of nature that causes objects with mass to attract each other.
• Universal Gravitation: Every point mass attracts every other point mass by a force acting along the line intersecting both points.
• Gravity on Earth:
  • The force of gravity on an object on the surface of the Earth is 9.8 m/s² (acceleration due to gravity).
  • Weight (W) is the force exerted on an object by gravity: W = mg, where m is the mass of the object.

Friction

• Definition: Friction is a force that opposes motion between two surfaces in contact.
• Types of Friction:
  • Static Friction: the force that prevents an object from moving when a force is applied.
  • Kinetic Friction: the force that opposes the motion of an object that is already moving.
  • Rolling Friction: the force that opposes the motion of an object that is rolling on a surface.
• Factors Affecting Friction:
  • Surface roughness: increased roughness increases friction.
  • Normal force: increased normal force increases friction.
  • Surface area: increased surface area in contact increases friction.

Newton's Laws

• An object at rest will remain at rest, and an object in motion will continue to move with a constant velocity, unless acted upon by an external force.
• Inertia is the tendency of an object to resist changes in its motion.
• Force (F) is equal to the mass (m) of an object multiplied by its acceleration (a): F = ma.
• The more massive an object, the more force is required to produce a given acceleration.
• For every action, there is an equal and opposite reaction.
• When two objects interact, the forces they exert on each other are equal in magnitude and opposite in direction.

Gravity

• Gravity is a fundamental force of nature that causes objects with mass to attract each other.
• Every point mass attracts every other point mass by a force acting along the line intersecting both points.
• The force of gravity on an object on the surface of the Earth is 9.8 m/s² (acceleration due to gravity).
• Weight (W) is the force exerted on an object by gravity: W = mg, where m is the mass of the object.

Friction

• Friction is a force that opposes motion between two surfaces in contact.
• Static friction is the force that prevents an object from moving when a force is applied.
• Kinetic friction is the force that opposes the motion of an object that is already moving.
• Rolling friction is the force that opposes the motion of an object that is rolling on a surface.
• Surface roughness increases friction.
• Increased normal force increases friction.
• Increased surface area in contact increases friction.