Contact and non contact

• What is the definition of a force?

  A push or pull acting on an object
• What are the two categories of forces?

  Contact forces and non-contact forces
• What is the unit of force?

  Newton
• What is a contact force?

  A force where two objects are physically touching
• What is an example of a contact force?

  Tension in a rope
• How does tension in a rope act in a tug of war?

  It pulls on the soldier
• What is air resistance?

  A contact force acting upwards on a sky diver
• What role does friction play when an airplane lands on water?

  It slows down the airplane
• What is the normal contact force?

  An upward force exerted by a surface
• How does the normal contact force relate to the weight of an object?

  It balances the downward weight force
• What defines a non-contact force?

  Forces where objects are physically separated
• What is an example of a non-contact force?

  Gravitational force
• How does gravitational force act between objects?

  It attracts all objects to each other
• What is electrostatic force?

  The force between two charged objects
• What happens to objects with opposite charges?

  They experience an electrostatic force of attraction
• What happens to objects with the same type of charge?

  They experience an electrostatic force of repulsion
• What is magnetic force?

  The force experienced in a magnetic field
• What will be covered in later videos regarding magnetic force?

  More details about magnetic force
• What are the examples of contact forces?

  • Tension in a rope
  • Friction
  • Air resistance
  • Normal contact force
• What are the examples of non-contact forces?

  • Gravitational force
  • Electrostatic force
  • Magnetic force