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 is the tendency of an object to resist changes in its motion.
• Second Law (F = ma):
  • The force (F) acting on an object is equal to the mass (m) of the object multiplied by its acceleration (a).
  • F = ma (force = mass x acceleration)
• Third Law (Action and Reaction):
  • When two objects interact, they apply forces to one another that are equal in magnitude and opposite in direction.

Friction

• Types of Friction:
  1. Static Friction: the force that prevents an object from moving when a force is applied to it.
  2. Kinetic Friction: the force that opposes an object's motion when it is already moving.
• Factors Affecting Friction:
  • Surface roughness
  • Normal force (force perpendicular to the surface)
  • Surface area in contact
• Frictional Forces:
  • Always oppose motion
  • Can be calculated using the formula: F = μN (frictional force = coefficient of friction x normal force)

Gravity

• Gravity as a Force:
  • A universal force that attracts two objects with mass towards each other.
  • Always acts towards the center of the Earth (or other celestial body).
• Gravity on Earth:
  • The force of gravity on Earth is approximately 9.8 N/kg (Newtons per kilogram).
  • This means an object with a mass of 1 kg will experience a force of 9.8 N downwards.

Momentum

• Momentum (p):
  • The product of an object's mass (m) and velocity (v).
  • p = mv (momentum = mass x velocity)
• Conservation of Momentum:
  • The total momentum before a collision is equal to the total momentum after a collision.
  • Momentum is conserved in closed systems.

Tension

• Tension Force:
  • A force that is transmitted through a string, rope, or wire when it is stretched or pulled.
  • Always acts along the length of the string, rope, or wire.
• Tension in Strings:
  • The tension force in a string is equal to the force applied to the string.
  • The tension force is the same at all points along the string.

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.
• The force (F) acting on an object is equal to the mass (m) of the object multiplied by its acceleration (a).
• F = ma (force = mass x acceleration)
• When two objects interact, they apply forces to one another that are equal in magnitude and opposite in direction.

Friction

• Static friction is the force that prevents an object from moving when a force is applied to it.
• Kinetic friction is the force that opposes an object's motion when it is already moving.
• Surface roughness, normal force, and surface area in contact affect friction.
• Frictional forces always oppose motion and can be calculated using the formula: F = μN (frictional force = coefficient of friction x normal force).

Gravity

• Gravity is a universal force that attracts two objects with mass towards each other.
• Gravity always acts towards the center of the Earth (or other celestial body).
• The force of gravity on Earth is approximately 9.8 N/kg (Newtons per kilogram).
• An object with a mass of 1 kg will experience a force of 9.8 N downwards on Earth.

Momentum

• Momentum is the product of an object's mass (m) and velocity (v).
• p = mv (momentum = mass x velocity)
• The total momentum before a collision is equal to the total momentum after a collision.
• Momentum is conserved in closed systems.

Tension

• Tension force is a force that is transmitted through a string, rope, or wire when it is stretched or pulled.
• Tension force always acts along the length of the string, rope, or wire.
• The tension force in a string is equal to the force applied to the string.
• The tension force is the same at all points along the string.

Test your understanding of Newton's three laws of motion, including the law of inertia, force and acceleration, and action and reaction.